Harrisburg School District
Chemistry Clickers
Leader’s Guide
Ted Gibbons
11/9/2010
Table of Contents
Unit One: The Science of Chemistry ...................... 3
Concept: The Scientific Method................................................................................................................ 3
Concept: Accuracy, Precision & Significant Figures .................................................................................. 8
Concept: Unit Conversions...................................................................................................................... 14
Summative Assessment – The Science of Chemistry .............................................................................. 18
Unit Two: Matter & Its Changes ......................... 22
Concept: Properties of Matter ................................................................................................................ 22
Concept: Classification of Matter ........................................................................................................... 28
Concept: Changes in Matter ................................................................................................................... 34
Summative Assessment – Matter & Its Changes .................................................................................... 39
Unit Three: Atoms .............................................. 45
Concept: History of Atomic Theory......................................................................................................... 45
Concept: Structure of the Atom.............................................................................................................. 51
Concept: Electrons and Their Arrangement ........................................................................................... 58
Summative Assessment - Atoms............................................................................................................. 64
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Unit One: The Science of Chemistry
Concept: The Scientific Method
Pre-Instruction Clicker Activities
Introduction
During this activity, students will read a scenario that contains a problem. After that, prior knowledge
about the scientific method will be assessed as they answer questions to determine an appropriate
problem statement/research question, hypothesis, variables and experiment pertaining to the scenario.
Questions can be answered individually or in groups and answers to the questions should be revealed
prior to moving on to the next question.
Scenario
William is trying to figure out what types of sunlight conditions are best for growing a bean plant.
Questions
1. What would be a good example of a research question for the above scenario?
a. What type of bean plant grows best in bright sunlight?
b. What are the best sunlight conditions for growing a bean plant?
c. What type of bean plant grows best in the shade?
d. Do bean plants grow best in slightly moist or very damp soil?
2. What would be a good example of a hypothesis?
a. Bean plants grow best in direct sunlight.
b. Bean plants need fertilizer to grow.
c. Bean plants need water for optimal growth.
d. Bean plants do not need sunlight to grow.
3. Give an example for an experiment that could be used to solve the bean problem:
a. Two bean plants could be placed in direct sunlight, each receiving different amounts of
water throughout the experiment
b. Two bean plants could be placed in the shade, each receiving different amounts of
fertilizer
c. One bean plant could be placed in direct sunlight and another bean plant could
receive indirect sunlight. (Indirect sunlight is created by using a filter that filters out
50% of the light)
d. One bean plant could be placed in direct sunlight while another bean plant could be
placed in a dark closet
4. What would be a nice example for a control variable?
a. A bean plant that is moved from direct sunlight to shade while the other plant in the
experiment does not move
b. A bean plant that stays in the sun and does not move while the other plant in the
experiment does move
c. The fact that a fixed amount of water is given to both bean plants throughout the
experiment
d. The fact that a varied amount of water is given to both bean plants throughout the
experiment
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5. What is an example of an independent variable or manipulated variable?
a. The amount of sunlight exposure given to each bean plant
b. The amount of bean growth
c. The average temperature in the room during the experiment
d. The average humidity in the air
6. What would be a good example of a dependent, or responding variable for this experiment?
a. The amount of sunlight coming through the window
b. The amount of bean growth
c. The average temperature in the room during the experiment
d. The average humidity in the air
Answers
1. B
2. A
3. C
4. C
5. A
6. B
Summary
After the last question is over, it is important to encourage the students, explaining that this was only a
pre-test, and that they should not feel bad if they did poorly. Point out how important it will be for
them to learn / review the steps of the scientific method in upcoming lessons so they will be ready for
more problems like the one found in this activity, where correct answers will eventually count toward
their class grade.
Clicker Activities for Instruction
Introduction
Here, students will listen and participate in a PowerPoint presentation on the scientific method. The
presentation will take a close look at the steps and terminology needed to understand the scientific
method. In addition, a science scenario that uses the scientific method to solve a problem will be
analyzed. Students will participate during the presentation by answering embedded clicker questions
pertaining to the scientific method throughout the lesson.
Questions
1. What is one important aspect of correctly defining a problem and/or developing a question for
the scientific method?
a. Using the results of an experiment to correctly define the problem
b. Making sure that the problem is easy to understand
c. Developing a question or problem that can be solved through experimentation
d. Developing a question or problem that can be solved without experimentation
2. Why are careful observations and research an important part of the scientific method?
a. Careful observations and research help you to discover the problem
b. Careful observations and research help you record experimental data
c. Careful observations and research help you share your results with the community
d. Careful observations and research help you develop a good hypothesis
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3. What would be a good hypothesis for the following problem / question? How is plant growth
affected by soil temperature?
a. If soil temperatures go down, then plant growth will decrease
b. If soil temperatures go up, then plant growth will increase
c. Soil temperature affects plant growth
d. Both a and b are good hypotheses
e. Both a and c are good hypotheses
4. An experiment must:
a. Be based on a specific procedure
b. Include a detailed materials list
c. Have a quantifiable outcome
d. All of the above
5. When you collect and analyze results, you must:
a. Modify the procedure if needed
b. Confirm the results by retesting
c. Include tables, graphs, and photographs
d. All of the above
6. Good conclusions for the scientific method always include:
a. Your personal feelings about the experimental results
b. A statement that accepts or rejects the hypothesis
c. Recommendations for further study and improvements to the procedure
d. Both a and c
e. Both b and c
7. When preparing to communicate the results of your experiment, you should:
a. Be prepared to present the project to an audience with the expectation that they will
ask questions
b. Be prepared to write a written report and create a display board only
c. Be prepared to present the project to an audience with the expectation that they will
not ask questions
8. What would be a good question for the “bread rising” scenario?
a. Yeast releases a gas as it feeds on sugar.
b. Does the amount of sugar used in the recipe affect the size of the bread loaf?
c. What kinds of things affect the size of the bread loaf?
d. What kinds of things affect the flavor of a large bread loaf?
9. If it is thought that more sugar causes bread to rise higher, what would be a good hypothesis
statement for this idea?
a. More sugar might cause bread to rise higher
b. Adding more sugar to bread will have a positive effect on the bread when it is baked
c. If more sugar is added, then bread will rise higher
10. An example of an independent variable, or manipulated variable , for the bread rising scenario
might be:
a. John is going to use a large amount of sugar in his experiment to see if it causes an
increase in the size of the bread loaf.
b. The size of the loaf of bread
c. The type of sugar used
d. John is going to use 25g., 50g., 100g., 250g., 500g. of sugar in his experiment.
11. An example of a dependent, or responding variable, for the bread rising scenario might be:
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a. John is going to use a large amount of sugar in his experiment to see if it causes an
increase in the size of the bread loaf.
b. The size of the loaf of bread
c. The type of sugar used
d. John is going to use 25g., 50g., 100g., 250g., 500g. of sugar in his experiment.
12. The control group for the bread rising scenario should be:
a. The same amount of sugar that John’s grandmother used
b. A larger amount of sugar than John’s grandmother used
c. A smaller amount of sugar than John’s grandmother used
d. A bread experiment containing no sugar
13. When analyzing the results of the bread experiment, which amount of sugar produced the best
results?
a. 25 g
b. 50 g
c. 100 g
d. 250 g
e. 500 g
14. Although John rejected his initial hypothesis, he decided to re-test using sugar amounts
between 50 and 100 grams. Based on his new results, what would be a good conclusion
statement?
a. John finds that a large amount of sugar produces a larger loaf
b. John finds that 50 grams of sugar produces the largest loaf
c. John finds that 70 grams of sugar produces the largest loaf
d. John finds that the amount of sugar does not affect the size of the loaf
Answers
7. C
8. D
9. D
10. D
11. D
12. E
13. A
14. B
15. C
16. D
17. B
18. A
19. B
20. C
Summary
Students will conclude this lesson by listing and briefly describing the 7 steps of the scientific method in
their science notebooks. Inform the students of the fact that they will be given a subsequent clicker quiz
whereby they will be required to identify each of the steps of the scientific method. In addition, they
will answer questions to determine an appropriate problem statement/research question, hypothesis,
variables and experiment pertaining to a given science scenario.
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Post-Instruction Clicker Activities
Introduction
For this activity, students should be given the scenario and questions (below) 1-3 days before they are
asked to perform the activity. Students will demonstrate what they have learned about the scientific
method as they use the scenario to answer questions about how to determine a problem
statement/research question, hypothesis, identify variables and design an experiment. Questions can be
answered individually or in groups and answers to the questions should be revealed prior to moving on
to the next question.
Scenario
Lisa just bought a new houseplant, but it didn’t come with any directions on how to water it. She
wonders if the amount of water given to the plant will affect its growth rate. Lisa goes back to the store
and buys 4 more plants just like the one she already has so that she can conduct a “plant watering
experiment” to find out an answer to her problem.
Questions
1. Based on Lisa’s houseplant scenario, what would be a good problem statement/research
question for her experiment?
a. What type of water helps plants to grow?
b. Does spring water or distilled water help plants to grow better?
c. Does the amount of water given to a houseplant affect its growth rate?
d. How does water affect plant growth?
2. What would be a good hypothesis for the houseplant scenario?
a. Houseplants grow best when they are watered
b. Houseplants grow best when they are watered every 3 days so that the soil remains
slightly damp about an inch below the surface
c. Houseplants grow best with a moderate amount of water
d. Houseplants grow better with spring water
3. What type of experiment should Lisa perform to solve her watering problem?
a. She should water each of her 5 plants the same but change the amount of sunlight that
each plant receives
b. She should change the type of water given to each of the plants
c. She should give all of the plants the same amount of water to dampen the soil, but
change the watering frequency for each of the plants. For example, one plant is
watered every day, one every other day, etc.
d. She should give all of the plants a different amount of water to dampen the soil and
change the watering frequency for each of the plants. For example, each plant is given a
different amount of water and one plant is watered every day, one every other day, etc.
4. A control for Lisa’s experiment could be:
a. One plant is given spring water while all the others are given distilled water
b. One plant is given distilled water while all the others are given spring water
c. Each plant is exposed to the same amount of sunlight throughout the experiment
d. Each plant is exposed to different amounts of sunlight throughout the experiment
5. What is an example of an independent variable or manipulated variable for the houseplant
scenario?
a. The amount of water given to each plant
b. The amount of growth recorded for each plant
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c. The fact that each plant is exposed to the same amount of sunlight
d. The fact that each plant is exposed to different amounts of sunlight
6. What would be a good example of a dependent, or responding variable for the houseplant
scenario?
a. The amount of water given to each plant
b. The amount of growth recorded for each plant
c. The fact that each plant is exposed to the same amount of sunlight
d. The fact that each plant is exposed to different amounts of sunlight
Answers
1. C
2. B
3. C
4. C
5. A
6. B
Summary
Summarize the activity by explaining to the students the importance of understanding the steps of the
scientific method, in addition to being able to read a scenario and apply the steps to solve an actual
problem. Students will continue to use the scientific method throughout the course of the year to solve
scientific problems. They will also use it if they choose to do a science fair project. Last, explain that
they should continue to study the steps and how to apply them to each of the previous scenarios that
we’ve studied as they prepare for a summative assessment on unit one.
Concept: Accuracy, Precision & Significant Figures
Pre-Instruction Clicker Activities
Introduction
For this activity, students will watch a demonstration whereby the teacher uses an uncalibrated triplebeam balance to weigh various objects. Using 3 trials for each item, the mass quantities should be
written on the board and an average mass should be calculated for each, without rounding. After using
the uncalibrated balance, the demonstration should be repeated after the balance has been calibrated.
Students will compare the results for each of the demonstrations answering prediction questions to test
their knowledge about the difference between accuracy and precision and the importance of significant
figures. Questions will be used to actively engage the students in the demonstration, and can be
answered individually or in groups.
Questions
1. During the demonstration that used the uncalibrated balance, the mass values that were
obtained had:
a. High accuracy but low precision
b. High precision but low accuracy
c. High accuracy and high precision
d. Low accuracy and low precision
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2. During the demonstration that used the calibrated balance, the mass values that were obtained
had:
a. High accuracy but low precision
b. High precision but low accuracy
c. High accuracy and high precision
d. Low accuracy and low precision
3. True or False: Significant figures represent digits within a number quantity that are known with
some degree of reliability.
a. True
b. False
4. For both demonstrations an average mass for each item was determined. True or False: When
the answers were calculated, the rules for rounding the final answer to the correct number of
significant figures were followed.
a. True
b. False
Answers
1. B
2. C
3. A
4. B
Summary
After students have answered all of the questions for this activity, explain the reasoning behind each of
the answers. However, because the students will be learning more about accuracy, precision and the
rules for significant figures in upcoming lessons, it is not necessary to spend too much time explaining
the answers. Instead, point out that the purpose for this activity was mainly to introduce the concepts
and establish why they are relevant when performing scientific measurements and/or calculations.
Clicker Activities for Instruction
Introduction
The following questions are designed to be used along with a lesson that explains the rules for
determining how many significant figures a number has. Students will listen to a PowerPoint
presentation that explains each of the rules for determining significant figures, and as the lesson
progresses, they will answer embedded clicker questions to illustrate their understanding of each new
rule. Questions can be answered individually or in groups.
Questions
1. According to the first rule for significant figures, how many significant figures are in the number
0.3434567?
a. 8
b. 7
2. According to the first rule for significant figures, the number 0.3434 has 4 significant figures.
a. True
b. False
3. According to the first rule for significant figures, how many significant figures are in the number
3.34 x 103?
a. 5
9
4.
5.
6.
7.
8.
9.
10.
11.
b. 3
c. 6
According to the second rule for significant figures, how many significant figures are in the
number 1305.5?
a. 5
b. 4
According to the second rule for significant figures, how many significant figures are in the
number 0.36007?
a. 5
b. 6
c. 3
According to the third rule for significant figures, how many significant figures are in the number
0.00000000000023?
a. 15
b. 14
c. 3
d. 2
According to the third rule for significant figures, how many significant figures are in the number
9.008 x 10-6?
a. 7
b. 4
c. 2
According to the fourth rule for significant figures, how many significant figures are in the
number 53.0?
a. 2
b. 3
According to the fourth rule for significant figures, how many significant figures are in the
number 7.5300000 x 105?
a. 8
b. 3
c. 11
According to the fifth rule for significant figures, how many significant figures are in the number
1600?
a. 2
b. 4
According to the fifth rule for significant figures, how many significant figures are in the number
1600.?
a. 2
b. 4
12. According to the fifth rule for significant figures, how many significant figures are in the
number 1.60 x 103
a. 2
b. 3
c. 6
Answers
1. B
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2. A
3. B
4. A
5. A
6. D
7. B
8. B
9. A
10. A
11. B
12. B
Summary
After completing the PowerPoint lesson on significant figures, students should be given additional
practice (similar to the embedded questions above) whereby they use the rules for significant figures to
identify the number of significant figures in a number. Although the above lesson and activity does not
address the rules for adding, subtracting, multiplying and dividing significant figures, it is recommended
that a lesson presenting these topics is included prior to administering the post-instruction clicker
questions. Further, students should be given the post-instruction clicker questions prior to the day that
the first response game on significant figures is administered so that they have a chance to study.
Post-Instruction Clicker Activities
Introduction
Here, students will participate in a first response game to test their proficiency at identifying the rules
for significant figures as well as their ability to use the rules quickly and correctly to solve problems. This
activity can be used as a formative assessment and also serves as a great review on significant figures
prior to the unit test. Questions can be answered individually or in groups.
Questions
1. What is the significant figure rounding rule for addition and subtraction?
a. Round to the GREATEST number of significant figures with relationship to the decimal
b. Round to the LEAST number of significant figures with relationship to the decimal
c. Round the answer to match the measurement with the LEAST total number of
significant figures
d. Round the answer to match the measurement with the GREATEST total number of
significant figures
2. What is the significant figure rounding rule for multiplication and division?
a. Round to the GREATEST number of significant figures with relationship to the decimal
b. Round to the LEAST number of significant figures with relationship to the decimal
c. Round the answer to match the measurement with the LEAST total number of
significant figures
d. Round the answer to match the measurement with the GREATEST total number of
significant figures
3. When counting significant figures:
a. All NON-ZERO numbers in a measurement ARE NOT significant
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b. All NON-ZERO numbers in a measurement ARE significant
4. When counting significant figures:
a. Zeros that are BETWEEN non-zero numbers ARE significant
b. Zeros that are BETWEEN non-zero numbers ARE NOT significant
5. When counting significant figures:
a. Zeros that are BEFORE non-zero numbers are NOT significant
b. Zeros that are BEFORE non-zero numbers ARE significant
6. When counting significant figures:
a. Zeros that are after a non-zero number and after the decimal ARE significant
b. Zeros that are after a non-zero number and after the decimal ARE NOT significant
7. Zeros after a non-zero number, but before the decimal are NOT significant,
a. Unless the decimal IS NOT written
b. Unless the decimal IS written
c. Under any circumstance
8. When rounding significant figures, look one digit past the number being rounded. Numbers less
than 5 are:
a. Dropped
b. Rounded up
9. When rounding significant figures, look one digit past the number being rounded. Numbers
greater than 5 are:
a. Dropped
b. Rounded up
10. If the last significant figure is an EVEN number and the next digit is a 5 and there are not other
non-zero digits,
a. Round up
b. Round down
11. If the last significant figure is an ODD number and the next digit is a 5 and there are not other
non-zero digits,
a. Round up
b. Round down
12. If the digit following the last significant figure is a 5 followed by a non-zero digit,
a. Round up
b. Round down
13. The masses of two objects are added together. The first mass is 36.46 grams and the mass of
the second object is 5.1234567 grams. When the rules for significant figures are used, the total
is:
a. 41.5834567 g
b. 41 g
c. 41.58 g
d. 42 g
14. Two items are measured and found to be 35.23552 cm and 0.490 cm. Using the rules for
significant figures, find the difference between the two measurements.
a. 34.74552 cm
b. 34.746 cm
c. 34.745 cm
d. 34.74 cm
15. If 0.6755 g is divided by 3.1 mL, the correct answer is:
a. 0.22 g/mL
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b. 0.21 g/mL
c. 0.2179032258 g/mL
d. 0.218 g/mL
16. If 5.23 cm is multiplied by 0.0026 cm, the correct answer is:
a. 0.013598 cm2
b. 0.013599 cm2
c. 0.014 cm2
d. 0.013 cm2
17. Round 33.25 grams to 3 significant figures:
a. 33.20 g
b. 33.2 g
c. 33.30 g
d. 33.3 g
18. Round 33.65000 cm to 3 significant figures:
a. 33.60 cm
b. 33.6 cm
c. 33.7000 cm
d. 33.7 cm
19. Round 64.75 mL to 3 significant figures:
a. 64.8 mL
b. 64.7 mL
c. 64.80 mL
d. 64.70 mL
20. Round 89.3500 km to 3 significant figures:
a. 89.35 km
b. 89.40 km
c. 89.4 km
d. 89.3 km
Answers
1. B
2. C
3. B
4. A
5. A
6. A
7. B
8. A
9. B
10. B
11. A
12. A
13. C
14. B
15. A
16. C
17. B
18. B
19. A
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20. C
Summary
Due to the fact that it is extremely tedious to learn and apply all of the rules for significant figures, it is
recommended that the students develop graphic organizers as a way of organizing the rules and for
studying. It is also recommended that the students are given additional exercises for class work and/or
homework as they prepare for the unit one assessment. It is important that the students have a firm
grasp of how to use significant figures as they will be using them to solve chemistry problems
throughout the course of the year. Next, students will continue to use significant figures as they use
dimensional analysis and conversion factors to perform unit conversions.
Concept: Unit Conversions
Pre-Instruction Clicker Activities
Introduction
In this activity, students will predict various metric measurements using a word bank of metric prefixes
to help them properly identify each measurement. For example, students will first look at an object, like
a 2 liter bottle of soda, and then they will have to decide whether the bottle represents 1 milliliter, 2
liters, 5 kiloliters, etc. Not only will this activity indicate the students’ understanding of metric prefixes,
it will also demonstrate their ability to estimate various quantities.
Questions
1. The length of one paperclip is represented by:
a. 1 millimeter
b. 2.5 centimeters
c. 3 dekameters
d. 10 kilometers
2. The volume capacity of a typical bottle of soda is most likely:
a. 2 liters
b. 8 liters
c. 1.5 milliliters
d. 1.5 hectoliters
3. The mass of one paperclip is probably about:
a. 1 milligram
b. 100 kilograms
c. 20 decigrams
d. 1 gram
4. A yardstick is similar in length to a:
a. gram stick
b. liter stick
c. meter stick
d. popsicle stick
Answers
1. B
2. A
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3. D
4. C
Summary
Following the introduction activity on unit conversions, the instructor will have a feel for the students’
familiarity with metric prefixes and their ability to correctly use them to estimate quantities. After this
activity, students will continue to learn about metric prefixes and how to convert between metric units
using the ladder method. During these lessons, students will be expected to answer embedded concept
questions and practice problems to demonstrate their understanding of how to convert measurements
from one metric unit to another.
Clicker Activities for Instruction
Introduction
Initially, students will be introduced to the “ladder method.” They will use the ladder method to convert
smaller units to larger units or larger units to smaller units mathematically or by simply moving the
decimal point. During the lesson, they will answer embedded concept questions and practice problems
to demonstrate their understanding of how to convert measurements from one metric unit to another.
Students can either answer the questions individually or they can work in groups.
Questions
1. The largest metric unit is the:
a. Hecto
b. Milli
c. Deci
d. Kilo
2. The smallest metric unit is the:
a. Hecto
b. Milli
c. Deci
d. Kilo
3. Meters, liters and grams are all examples of:
a. Larger units
b. Smaller units
c. Basic units
d. Length units
4. The metric prefix “hecto” is equal to how many basic units?
a. 1000
b. 100
c. 0.1
d. 0.001
5. The metric prefix “milli” is equal to how many basic units?
a. 1000
b. 100
c. 0.1
d. 0.001
6. When using the ladder method to convert from a smaller unit to a larger unit, one must:
a. Move the decimal point to the left or divide
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7.
8.
9.
10.
11.
12.
b. Move the decimal point to the right or divide
c. Move the decimal point to the left or multiply
d. Move the decimal point to the right or multiply
When using the ladder method to convert from a larger unit to a smaller unit, one must:
a. Move the decimal point to the left or divide
b. Move the decimal point to the right or divide
c. Move the decimal point to the left or multiply
d. Move the decimal point to the right or multiply
The first step of the ladder method is to:
a. Count the “jumps” to your ending point
b. Determine your starting point
c. Move the decimal the same number of jumps in the same direction
The second step of the ladder method is to:
a. Count the “jumps” to your ending point
b. Determine your starting point
c. Move the decimal the same number of jumps in the same direction
The third step of the ladder method is to:
a. Count the “jumps” to your ending point
b. Determine your starting point
c. Move the decimal the same number of jumps in the same direction
Starting with the largest unit and ending with the smallest, which of the following lists all of the
metric prefixes in the correct order?
a. kilo, hecto, deka, basic unit, deci, centi, milli
b. milli, centi, deci, basic unit, deka, hecto, kilo
c. kilo, hecto, deci, basic unit, deka, centi, milli
d. milli, centi, deci, basic unit, deka, hecto, kilo
Which of the following items would be the heaviest?
a. A box of rocks weighing 1000 grams
b. A box of feathers weighing 1.0 kilogram
c. A box of lead weighing 1000 milligrams
d. Both a and b
Answers
1. D
2. B
3. C
4. B
5. D
6. A
7. D
8. B
9. A
10. C
11. A
12. D
Summary
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After the lesson on metric conversions and the ladder method, it is recommended that students receive
additional practice on performing metric conversions. Before the next clicker activity students will learn
dimensional analysis as well as how to use conversion factors to perform unit conversions. These
concepts are needed in addition to the ladder method, due to the fact that conversions between units,
other than metric units, are often necessary. For example, sometimes it is necessary to convert inches
to centimeters, using dimensional analysis and a conversion factor to obtain the result.
Post-Instruction Clicker Activities
Introduction
During this activity students will participate in a first response game to test their understanding of
metric prefixes, the rules for unit conversions, dimensional analysis, conversion factors, and most
important, their ability to use these concepts and rules to efficiently solve problems. Whether working
individually or as part of a group, a first response game is a great way for students to take a formative
assessment and/or review for a test. Due to the fact that students' study habits are positively affected
when clicker questions are pre-assigned 1-3 days before a clicker activity is administered, similar
questions should be distributed ahead of time. In addition, it is also important to note that there are
only 4 questions due to the fact the questions are multi-step problems and take longer to solve.
Conversion Factors (note: the following conversion factors should be made available for the students
before they are given the questions; if a conversion factor is needed but does not appear on the list,
the conversion factor is assumed to be “common knowledge”)
1 inch = 2.54 cm exactly
1 cc = 1 cm^3 = 1 mL exactly
Questions
1. If a car ride takes 95 minutes, how many hours does that represent?
a. 1.58 hours
b. 1.6 hours
c. 1.583333333 hours
d. 5700 hours
2. A student determines the the density of a certain material is 8.92 g/cm^3. What would the
density of the material be in g/L?
a. 8920 g/L
b. 0.00892 g/L
c. 892 g/L
d. 0.0892 g/L
3. Imagine that water is leaking from a swimming pool, at a rate of 2.4 ml/hr. If this rate remains
constant, how many liters of water will be lost in a week?
a. 25 L/wk
b. 0.04032 L/wk
c. 0.4032 L/wk
d. 0.40 L/wk
4. A box measures 1.56 ft in length, 0.02275 yd in width and 3.935 inches in height. What is its
volume in cubic centimeters?
a. 988.6342062 cm^3
b. 989 cm^3
17
c. 9.89 x 10^2 cm^3
d. Both b and c
Answers
1. B
2. A
3. D
4. D
Summary
At this point, students have answered clicker questions on metric prefixes and on the rules for
converting between metric units. They have also answered questions whereby they have demonstrated
how to perform unit conversions using dimensional analysis and conversion factors. As a result, they
have now completed questions on all of the major concepts found in unit one, The Science of
Chemistry,” and are ready for a summative assessment on unit one. Students should study their notes
on each of the concepts and re-work practice problems to prepare for the assessment.
Summative Assessment – The Science of Chemistry
Introduction
The following assessment can be used in addition to, or in place of, a written summative assessment on
the concepts found in unit one. It will include questions selected from previous unit one clicker
activities and must be completed individually. Students should study their notes on each of the
concepts and re-work practice problems to prepare for the assessment.
Scenario (questions 1-6)
Lisa just bought a new houseplant, but it didn’t come with any directions on how to water it. She
wonders if the amount of water given to the plant will affect its growth rate. Lisa goes back to the store
and buys 4 more plants just like the one she already has so that she can conduct a “plant watering
experiment” to find out an answer to her problem.
Questions
1. Based on Lisa’s houseplant scenario, what would be a good problem statement/research
question for her experiment?
a. What type of water helps plants to grow?
b. Does spring water or distilled water help plants to grow better?
c. Does the amount of water given to a houseplant affect its growth rate?
d. How does water affect plant growth?
2. What would be a good hypothesis for the houseplant scenario?
a. Houseplants grow best when they are watered
b. Houseplants grow best when they are watered every 3 days so that the soil remains
slightly damp about an inch below the surface
c. Houseplants grow best with a moderate amount of water
d. Houseplants grow better with spring water
3. What type of experiment should Lisa perform to solve her watering problem?
a. She should water each of her 5 plants the same but change the amount of sunlight that
each plant receives
18
4.
5.
6.
7.
8.
9.
10.
11.
12.
19
b. She should change the type of water given to each of the plants
c. She should give all of the plants the same amount of water to dampen the soil, but
change the watering frequency for each of the plants. For example, one plant is
watered every day, one every other day, etc.
d. She should give all of the plants a different amount of water to dampen the soil and
change the watering frequency for each of the plants. For example, each plant is given a
different amount of water and one plant is watered every day, one every other day, etc.
A control for Lisa’s experiment could be:
a. One plant is given spring water while all the others are given distilled water
b. One plant is given distilled water while all the others are given spring water
c. Each plant is exposed to the same amount of sunlight throughout the experiment
d. Each plant is exposed to different amounts of sunlight throughout the experiment
What is an example of an independent variable or manipulated variable for the houseplant
scenario?
a. The amount of water given to each plant
b. The amount of growth recorded for each plant
c. The fact that each plant is exposed to the same amount of sunlight
d. The fact that each plant is exposed to different amounts of sunlight
What would be a good example of a dependent, or responding variable for the houseplant
scenario?
a. The amount of water given to each plant
b. The amount of growth recorded for each plant
c. The fact that each plant is exposed to the same amount of sunlight
d. The fact that each plant is exposed to different amounts of sunlight
What is the significant figure rounding rule for addition and subtraction?
a. Round to the GREATEST number of significant figures with relationship to the decimal
b. Round to the LEAST number of significant figures with relationship to the decimal
c. Round the answer to match the measurement with the LEAST total number of
significant figures
d. Round the answer to match the measurement with the GREATEST total number of
significant figures
What is the significant figure rounding rule for multiplication and division?
a. Round to the GREATEST number of significant figures with relationship to the decimal
b. Round to the LEAST number of significant figures with relationship to the decimal
c. Round the answer to match the measurement with the LEAST total number of
significant figures
d. Round the answer to match the measurement with the GREATEST total number of
significant figures
When counting significant figures:
a. All NON-ZERO numbers in a measurement ARE NOT significant
b. All NON-ZERO numbers in a measurement ARE significant
When counting significant figures:
a. Zeros that are BETWEEN non-zero numbers ARE significant
b. Zeros that are BETWEEN non-zero numbers ARE NOT significant
When counting significant figures:
a. Zeros that are BEFORE non-zero numbers are NOT significant
b. Zeros that are BEFORE non-zero numbers ARE significant
When counting significant figures:
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
20
a. Zeros that are after a non-zero number and after the decimal ARE significant
b. Zeros that are after a non-zero number and after the decimal ARE NOT significant
Zeros after a non-zero number, but before the decimal are NOT significant,
a. Unless the decimal IS NOT written
b. Unless the decimal IS written
c. Under any circumstance
When rounding significant figures, look one digit past the number being rounded. Numbers less
than 5 are:
a. Dropped
b. Rounded up
When rounding significant figures, look one digit past the number being rounded. Numbers
greater than 5 are:
a. Dropped
b. Rounded up
If the last significant figure is an EVEN number and the next digit is a 5 and there are not other
non-zero digits,
a. Round up
b. Round down
If the last significant figure is an ODD number and the next digit is a 5 and there are not other
non-zero digits,
a. Round up
b. Round down
If the digit following the last significant figure is a 5 followed by a non-zero digit,
a. Round up
b. Round down
The masses of two objects are added together. The first mass is 36.46 grams and the mass of
the second object is 5.1234567 grams. When the rules for significant figures are used, the total
is:
a. 41.5834567 g
b. 41 g
c. 41.58 g
d. 42 g
Two items are measured and found to be 35.23552 cm and 0.490 cm. Using the rules for
significant figures, find the difference between the two measurements.
a. 34.74552 cm
b. 34.746 cm
c. 34.745 cm
d. 34.74 cm
If 0.6755 g is divided by 3.1 mL, the correct answer is:
a. 0.22 g/mL
b. 0.21 g/mL
c. 0.2179032258 g/mL
d. 0.218 g/mL
If 5.23 cm is multiplied by 0.0026 cm, the correct answer is:
a. 0.013598 cm2
b. 0.013599 cm2
c. 0.014 cm2
d. 0.013 cm2
23. Round 33.25 grams to 3 significant figures:
a. 33.20 g
b. 33.2 g
c. 33.30 g
d. 33.3 g
24. Round 33.65000 cm to 3 significant figures:
a. 33.60 cm
b. 33.6 cm
c. 33.7000 cm
d. 33.7 cm
25. Round 64.75 mL to 3 significant figures:
a. 64.8 mL
b. 64.7 mL
c. 64.80 mL
d. 64.70 mL
26. Round 89.3500 km to 3 significant figures:
a. 89.35 km
b. 89.40 km
c. 89.4 km
d. 89.3 km
27. If a car ride takes 95 minutes, how many hours does that represent?
a. 1.58 hours
b. 1.6 hours
c. 1.583333333 hours
d. 5700 hours
28. A student determines the the density of a certain material is 8.92 g/cm^3. What would the
density of the material be in g/L?
a. 8920 g/L
b. 0.00892 g/L
c. 892 g/L
d. 0.0892 g/L
29. Imagine that water is leaking from a swimming pool, at a rate of 2.4 ml/hr. If this rate remains
constant, how many liters of water will be lost in a week?
a. 25 L/wk
b. 0.04032 L/wk
c. 0.4032 L/wk
d. 0.40 L/wk
30. A box measures 1.56 ft in length, 0.02275 yd in width and 3.935 inches in height. What is its
volume in cubic centimeters?
a. 988.6342062 cm^3
b. 989 cm^3
c. 9.89 x 10^2 cm^3
d. Both b and c
Answers
1. C
2. B
3. C
21
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
C
A
B
B
C
B
A
A
A
B
A
B
B
A
A
C
B
A
C
B
B
A
C
B
A
D
D
Summary
Students have now successfully completed all of the questions for unit one, The Science of Chemistry.
They learned how chemistry can be used to describe natural phenomena by learning and applying the
following concepts: the scientific method, accuracy and precision, significant figures and unit
conversions. Next, the students will be learning about how matter can be described, classified and
changed in unit two, Matter and Its Changes. The concepts that they will be studying in unit two are the
properties of matter, the classification of matter and changes in matter.
Unit Two: Matter & Its Changes
Concept: Properties of Matter
Pre-Instruction Clicker Activities
22
Introduction
For the first activity of unit two, students should be given a vocabulary list ahead of time. That way,
they will be able to research and/or discuss the meanings of the words prior to the clicker activity.
Giving the students a vocabulary quiz prior to teaching the meanings of the words will increase
engagement before instruction even begins. Although the questions can be answered individually or in
groups, it is recommended that they be answered in groups so that the students can take advantage of
peer instruction as they are then able to discuss the meanings of the new words before answering the
clicker questions.
Questions
1. Which of the following best defines the word “chemistry”?
a. The science of the composition, structure, properties, and reactions of matter,
especially of atomic and molecular systems
b. The study of the natural or material world and phenomena; natural philosophy
c. The science of life and of living organisms, including their structure, function, growth,
origin, evolution, and distribution. It includes botany and zoology and all their
subdivisions
d. The scientific study of the origin, history, and structure of the earth
2. A substance is:
a. A composition of two or more substances that are not chemically combined with each
other and are capable of being separated
b. A pure, macroscopically homogeneous substance consisting of atoms or ions of two or
more different elements in definite proportions that cannot be separated by physical
means
c. A specific type of matter, especially a homogeneous material with a definite
composition
d. A system in which finely divided particles, which are approximately 10 to 10,000
angstroms in size, are dispersed within a continuous medium in a manner that prevents
them from being filtered easily or settled rapidly
3. A chemical property is best defined as:
a. a basic or essential attribute shared by all members of a class; "a study of the physical
properties of atomic particles"
b. a property used to characterize materials in reactions that change their identity
c. any property used to characterize matter and energy and their interactions
d. the degree of hotness or coldness of a body or environment (corresponding to its
molecular activity)
4. A physical property is best defined as:
a. a basic or essential attribute shared by all members of a class; "a study of the physical
properties of atomic particles"
b. a property used to characterize materials in reactions that change their identity
c. any property used to characterize matter and energy and their interactions
d. the degree of hotness or coldness of a body or environment (corresponding to its
molecular activity)
23
5. An intensive property of matter is:
a. A property that depends on the amount of matter present
b. A property that does not depend on the amount of matter present
c. A measurement of the gravitational force of attraction of the earth acting on an object
d. A measurement of the amount of space a substance occupies
6. An extensive property of matter is:
a. A property that depends on the amount of matter present
b. A property that does not depend on the amount of matter present
c. A measurement of the gravitational force of attraction of the earth acting on an object
d. A measurement of the amount of space a substance occupies
7. Density is:
a. The amount of three dimensional space that any solid, liquid or gas object occupies
b. The amount of matter that an object contains
c. The amount of matter contained in a given amount of space
d. The upward force on an object produced by the surrounding liquid or gas in which it is
fully or partially immersed, due to the pressure difference of the fluid between the top
and bottom of the object
8. Mass is:
a. The amount of three dimensional space that any solid, liquid or gas object occupies
b. The amount of matter that an object contains
c. The amount of matter contained in a given amount of space
d. The upward force on an object produced by the surrounding liquid or gas in which it is
fully or partially immersed, due to the pressure difference of the fluid between the top
and bottom of the object
9. Volume is:
a. The amount of three dimensional space that any solid, liquid or gas object occupies
b. The amount of matter that an object contains
c. The amount of matter contained in a given amount of space
d. The upward force on an object produced by the surrounding liquid or gas in which it is
fully or partially immersed, due to the pressure difference of the fluid between the top
and bottom of the object
Answers
1. A
2. C
3. B
4. C
5. B
6. A
7. C
8. B
9. A
24
Summary
After the vocabulary activity is finished, the definitions for the words should be taught as part of the
lesson on the properties of matter. As a result of the vocabulary preview clicker activity, the students
will be more engaged in this lesson. Once the students have learned the new words and the basic
concepts for the properties of matter, they will be ready to apply their knowledge. They will do this in
the next activity where they will be identifying unknown samples of matter based on each substance’s
physical and chemical properties.
Clicker Activities for Instruction
Introduction
During this activity, students will look at 3 different unknown chemical samples and answer clicker
questions about the identities of the samples. The purpose of this activity is to engage the students
before they actually do the lab. While looking at the samples, they will also be allowed to look at a
physical and chemical properties chart to help them make their predictions. By doing this activity prior
to the lab, they will be more engaged during the lab as they will want to determine if their predictions
were correct. The clicker questions can be answered individually or in groups.
(Notes: It is recommended that the students write down reasons for their answers, due to the fact that
the questions are multiple-choice. This way, they will be forced to apply what they have learned about
physical and chemical properties as they refer to the properties chart. In addition, the “right answers”
to the following questions is based on whichever “unknown samples” the teacher decides to use and do
not have to match the choices below. If the teacher decides to use different unknowns, the questions
can be adjusted accordingly.)
Questions
1. Exhibit A is a sample of:
a. Wood
b. Copper
c. Calcium
d. Iron
2. Exhibit B is a sample of:
a. Lead
b. Aluminum
c. Calcium
d. Copper
3. Exhibit C is a sample of:
a. Wood
b. Aluminum
c. Calcium
d. Iron
Answers
1. A
2. C
3. D
25
Summary
After the students have made their predictions, they will be ready to perform the lab activities to
determine the identities of the unknown chemicals. Next, students will learn about intensive and
extensive properties of matter before moving on to the post-instruction clicker activities. To improve
the students’ study habits, the post-instruction clicker questions should be distributed ahead of time.
The questions will be identical to the pre-instruction clicker questions and will serve as a formative
assessment to test individual learning of key vocabulary terms.
Post-Instruction Clicker Activities
Introduction
Here, students will be answering the same vocabulary questions that they answered for the preinstruction clicker activities. After already being exposed to the words on the pre-instruction clicker
activity, learning about them in class and applying them in the lab, at this point, they should have a firm
understanding of the meanings of the words. This activity serves as a good formative assessment and
can be answered individually or in groups.
Questions
1. Which of the following best defines the word “chemistry”?
a. The science of the composition, structure, properties, and reactions of matter,
especially of atomic and molecular systems
b. The study of the natural or material world and phenomena; natural philosophy
c. The science of life and of living organisms, including their structure, function, growth,
origin, evolution, and distribution. It includes botany and zoology and all their
subdivisions
d. The scientific study of the origin, history, and structure of the earth
2. A substance is:
a. A composition of two or more substances that are not chemically combined with each
other and are capable of being separated
b. A pure, macroscopically homogeneous substance consisting of atoms or ions of two or
more different elements in definite proportions that cannot be separated by physical
means
c. A specific type of matter, especially a homogeneous material with a definite
composition
d. A system in which finely divided particles, which are approximately 10 to 10,000
angstroms in size, are dispersed within a continuous medium in a manner that prevents
them from being filtered easily or settled rapidly
3. A chemical property is best defined as:
a. a basic or essential attribute shared by all members of a class; "a study of the physical
properties of atomic particles"
b. a property used to characterize materials in reactions that change their identity
c. any property used to characterize matter and energy and their interactions
d. the degree of hotness or coldness of a body or environment (corresponding to its
molecular activity)
26
4. A physical property is best defined as:
a. a basic or essential attribute shared by all members of a class; "a study of the physical
properties of atomic particles"
b. a property used to characterize materials in reactions that change their identity
c. any property used to characterize matter and energy and their interactions
d. the degree of hotness or coldness of a body or environment (corresponding to its
molecular activity)
5. An intensive property of matter is:
a. A property that depends on the amount of matter present
b. A property that does not depend on the amount of matter present
c. A measurement of the gravitational force of attraction of the earth acting on an object
d. A measurement of the amount of space a substance occupies
6. An extensive property of matter is:
a. A property that depends on the amount of matter present
b. A property that does not depend on the amount of matter present
c. A measurement of the gravitational force of attraction of the earth acting on an object
d. A measurement of the amount of space a substance occupies
7. Density is:
a. The amount of three dimensional space that any solid, liquid or gas object occupies
b. The amount of matter that an object contains
c. The amount of matter contained in a given amount of space
d. The upward force on an object produced by the surrounding liquid or gas in which it is
fully or partially immersed, due to the pressure difference of the fluid between the top
and bottom of the object
8. Mass is:
a. The amount of three dimensional space that any solid, liquid or gas object occupies
b. The amount of matter that an object contains
c. The amount of matter contained in a given amount of space
d. The upward force on an object produced by the surrounding liquid or gas in which it is
fully or partially immersed, due to the pressure difference of the fluid between the top
and bottom of the object
9. Volume is:
a. The amount of three dimensional space that any solid, liquid or gas object occupies
b. The amount of matter that an object contains
c. The amount of matter contained in a given amount of space
d. The upward force on an object produced by the surrounding liquid or gas in which it is
fully or partially immersed, due to the pressure difference of the fluid between the top
and bottom of the object
Answers
1. A
2. C
27
3.
4.
5.
6.
7.
8.
9.
B
C
B
A
C
B
A
Summary
After this activity has culminated, students will have a firm understanding of the meanings of the words
for The Properties of Matter Concept. Following this activity, students will begin to prepare for a
prediction clicker activity on the second concept of this unit, The Classification of Matter. Prior to the
pre-instruction activity for the next concept, students should be given the prediction questions to
consider ahead of time. This way, they will have the opportunity to think about and research their
predictions before the activity begins. To see these questions, please look below to the pre-instruction
clicker activity questions for The Classification of Matter.
Concept: Classification of Matter
Pre-Instruction Clicker Activities
Introduction
During this activity, students will be given the opportunity to make predictions about how different
forms of matter are classified. They will not have learned about the difference between pure
substances and mixtures (unless they took the initiative to research the difference prior to this activity),
but instead, they will make predictions based on their prior knowledge and based on the results of their
observations and peer discussions. It is important to note that although this activity does not include
questions about different types of mixtures, students will be asked about this in the post-instruction
questions. Students can work individually or in groups to examine samples of matter that will either be
classified as pure substances or mixtures.
Questions
1. Is air an example of a pure substance or a mixture?
a. Pure substance
b. Mixture
2. Is hydrogen an example of a pure substance or a mixture?
a. Pure substance
b. Mixture
3. Is rubbing alcohol an example of a pure substance or a mixture?
a. Pure substance
b. Mixture
4. Is carbon an example of a pure substance or a mixture?
a. Pure substance
b. Mixture
5. Is methane an example of a pure substance or a mixture?
28
6.
7.
8.
9.
10.
a. Pure substance
b. Mixture
Is soil an example of a pure substance or a mixture?
a. Pure substance
b. Mixture
Is gold an example of a pure substance or a mixture?
a. Pure substance
b. Mixture
Is carbon dioxide an example of a pure substance or a mixture?
a. Pure substance
b. Mixture
Is salad a good example of a pure substance or a mixture?
a. Pure substance
b. Mixture
Is pure water a good example of a pure substance or a mixture?
a. Pure substance
b. Mixture
Answers
1. B
2. A
3. B
4. A
5. A
6. B
7. A
8. A
9. B
10. A
Summary
The pre-instruction activity on The Classification of Matter is an excellent introduction to this concept.
This is because students will more than likely answer many of the seemingly “easy” pre-instruction
questions wrong, leaving them anxious for an explanation. They will be surprised to learn about the
criteria that are used to distinguish between a pure substance and a mixture. As part of that lesson, it is
recommended that the students create a type of flow chart / graphic organizer that lays out the steps
for classifying matter. For the next clicker activity, students will apply what they have learned and
reattempt to properly identify different types of matter as either a pure substance or a mixture.
Clicker Activities for Instruction
Introduction
29
Here, students will answer embedded classification questions as they go through a lesson on the
classification of matter. It is recommended that the lesson distinguishes between pure substances and
mixtures, in addition to explaining the different types of mixtures that are possible. The questions will
be used as a formative assessment to check how well students are able to classify matter into different
categories based on their properties. Questions can be answered individually or in groups.
Questions
1. The element carbon is a good example of a:
a. Pure substance
b. Mixture
2. The compound CO2 is a good example of a:
a. Pure substance
b. Mixture
3. Mixtures can be:
a. Either homogeneous or heterogeneous
b. Either homozygous or heterozygous
c. Composed of only one type of element
d. Composed of only one type of compound
4. True or False: Mixtures can be solutions
a. True
b. False
5. Three examples of different types of mixtures that are based upon the size of the solute are:
a. Suspension, colloidal and solution
b. Suspension, heterogeneous and solution
c. Suspension, homogeneous and solution
d. Both b and c
6. True or False: Homogeneous mixtures are also known as solutions
a. True
b. False
7. A good example of a suspension mixture is a bottle of:
a. Sugar water
b. Oil and water
c. Milk
d. Food coloring and water
8. A good example of a colloidal mixture is a container of:
a. Hair spray
b. Smoke
c. Whipped cream
d. Blood
e. All of the above
9. A good example of a solution is:
a. Oxygen in water
b. Salt in water
c. Marbles in water
d. Both a and b
30
10. You can separate a simple mixture by:
a. Physical means
b. Chemical means only
c. Adding a water softener
d. Heating the solution over an open flame
11. When you add material to a gas or liquid, the material you add is called the _________ and the
material you are adding to is called the __________.
a. solvent, solute
b. solute, solvent
c. mixing agent, dissolving agent
d. dissolving agent, mixing agent
Answers
1. A
2. A
3. A
4. A
5. A
6. A
7. B
8. E
9. D
10. A
11. B
Summary
Now that the students have finished learning about how to classify matter, they are ready for the next
activity which will apply their classification skills. During the next activity they will take what they have
learned about pure substances and different types of mixtures and analyze a scenario about different
substances that are accidentally combined during a lab accident. They will need to classify the
substances and answer questions about the nature of the substances in addition to theorizing on how
the substances can be separated.
Post-Instruction Clicker Activities
Introduction
For the post-instruction activities, students will apply what they have learned about how to differentiate
between pure substances and mixtures, in addition to being able to classify different types of mixtures.
They will do this by analyzing a scenario whereby several substances are combined. They will have to
decide if the new combination, and its individual components, represents pure substances or mixtures,
and the best techniques, if possible, for separating the substances. Students can work individually or in
groups as they are formatively assessed on their ability to classify matter.
Scenario
Daishaun and Shaniqua were both carrying lab materials to their individual lab stations. Daishaun was
carrying a container of sand in one hand and a container of salt in the other while Shaniqua was carrying
31
a container of iron filings in one hand and a container of water in the other. Unfortunately, they were
running in the lab and accidentally ran into each other. Because all of the containers were open, all of
the materials spilled onto the floor into one big pile. Answer the following questions to determine
which part(s) of their mishap created a pure substance and/or mixture and how any of these things, if
possible, can be separated.
Questions
1. When the sand and salt combined, which of the following formed?
a. Pure substance
b. Mixture
2. The sand by itself, also known as SiO2 or silicone dioxide, represents a:
a. Pure substance
b. Mixture
3. When the sand and iron filings combined, which of the following formed?
a. Pure substance
b. Mixture
4. When the salt and the iron filings combined, which of the following formed?
a. Pure substance
b. Mixture
5. The water by itself, also known as H2O or dihydrogen monoxide, represents a:
a. Pure substance
b. Mixture
6. When the water and the iron filings combined, which of the following formed?
a. Pure substance
b. Mixture
7. When the water and the salt combined, which of the following formed?
a. Pure substance
b. Mixture
8. The combination of the water, sand, salt and iron filings created a:
a. Pure substance
b. Mixture
9. The combination of water, sand, salt and iron filings created a:
a. Homogeneous mixture
b. Heterogeneous mixture
10. Which of the following can be separated without a chemical change?
a. Pure substance
b. Mixture
11. Which of the following techniques would be best suited for removing the iron filings from the
pile?
a. Magnifying glass and tweezers
b. Power washer
c. Microscope
32
d. Magnet
12. Assuming that the iron filings are already gone, which of the following techniques would be best
suited for removing the sand from the pile?
a. Carefully gather the wet sand and pour it into a funnel with filter paper over a flask
b. Use paper towels and a hair dryer to dry up all of the water so that you can easily
sweep-up all of the sand
c. Use a magnifying glass and tweezers to separate the sand from the salt
d. Use the sticky side of some duct tape to remove the sand from the pile
13. Assuming that the iron filings and the sand are already gone, which of the following techniques
would be best suited for removing the salt from the water?
a. Use a magnifying glass and tweezers to separate the salt from the water
b. Use a sponge to collect all of the water, squeezing every last drop into a funnel with
filter paper over a flask
c. Boil the water in the flask, leaving behind only salt
d. Both a and c
e. Both b and c
14. The combination of salt and water created a:
a. Homogeneous mixture
b. Heterogeneous mixture
c. Colloid
d. Suspension
Answers
1. B
2. A
3. B
4. B
5. A
6. B
7. B
8. B
9. B
10. B
11. D
12. A
13. E
14. A
Summary
Students should now have an excellent understanding of the properties of matter and how to classify
matter. They learned how to do this based on a substance’s physical and chemical properties. They also
learned how to differentiate between pure substances and different types of mixtures. In the next
33
section, they will learn about the different changes that matter undergoes. Prior to the first clicker
activity, students should be given the vocabulary words for the new concept (see below). That way,
they can prepare for the activity in advance, which will have a positive effect on their study habits.
Concept: Changes in Matter
Pre-Instruction Clicker Activities
Introduction
Students will be introduced to the words that are used to describe some of the changes that matter
undergoes. By previewing the words prior to the lesson, they will be more engaged during the teaching
of the new words and related concepts. During the activity, students can work individually or use peer
instruction to discuss possible meanings of words. Alternatively, if they are given the words ahead of
time, the activity can be used as a type of homework quiz.
Questions
1. A change that involves the mixing of two or more chemicals, refers to a:
a. Chemical change
b. Physical change
c. Phase change
d. Not enough information
2. During a ___________ _________ there is a chemical reaction, a new substance is formed and
energy is either given off or absorbed.
a. Physical change
b. Chemical change
c. Phase change
d. Endothermic change
3. A __________ ________ in a substance doesn’t change what the substance is.
a. Physical change
b. Chemical change
c. Phase change
d. Exothermic change
4. A phase change happens when:
a. a sample of matter changes from one state (solid, liquid or gas) to another while also
producing a change in chemical composition.
b. a sample of matter changes from one state (solid, liquid or gas) to another without
producing a change in chemical composition.
5. A chemical reaction is:
a. A change in which a substance (or substances) is changed into one or more new
substances
b. A change in which a substance (or substances) undergoes a phase change
34
c. A change that must involve combustion
d. A change that occurs when matter is exposed to temperatures below absolute zero
6. Energy refers to:
a. The rate at which work is done
b. The ability to do work
c. A measure of the intensity of heat
d. Force per unit area
7. During an exothermic reaction:
a. Heat does not flow in or out of the system
b. Heat exits the system
c. Heat enters the system
d. Heat is intense
8. During an endothermic reaction:
a. Heat does not flow in or out of the system
b. Heat exits the system
c. Heat enters the system
d. Heat is intense
Answers
1. D
2. B
3. A
4. B
5. A
6. B
7. B
8. C
Summary
Now that the students have been exposed to the words that describe changes in matter, they are ready
for a lesson about physical and chemical changes. They are also ready to learn about how energy is
transferred during chemical reactions. After students have learned these things, they will be ready for a
lab activity whereby they will perform various physical and chemical changes. For the next clicker
activity, and prior to the lab, students will make predictions about the upcoming lab experiments. For
example, they will predict whether the changes are going to be physical or chemical, and whether they
are going to be exothermic or endothermic.
Clicker Activities for Instruction
Introduction
For this activity, students will be making laboratory experiment predictions. To improve their study
habits the questions should be handed out 1-3 days prior to the activity. For the questions, students will
35
predict whether changes that are going to take place in the upcoming lab experiments are going to be
physical or chemical, and whether they are going to be exothermic or endothermic. Since students will
be working in groups during the lab activity, it is recommended that they work in the same groups to
answer the prediction questions. However, students may work individually if they prefer. In addition,
after the students have completed the lab exercises, the teacher may want to assess their learning by
allowing the students to retake the clicker quiz while discussing the lab results.
Questions
1. Melting ice cubes is a:
a. Physical and exothermic change
b. Physical and endothermic change
c. Chemical and exothermic change
d. Chemical and endothermic change
2. Burning a candle is a:
a. Physical and exothermic change
b. Physical and endothermic change
c. Chemical and exothermic change
d. Chemical and endothermic change
3. Rusting steel wool (by adding steel wool to bleach and hydrogen peroxide) is a:
a. Physical and exothermic change
b. Physical and endothermic change
c. Chemical and exothermic change
d. Chemical and endothermic change
4. Mixing water and potassium chloride (a type of salt) produces a:
a. Physical and exothermic change
b. Physical and endothermic change
c. Chemical and exothermic change
d. Chemical and endothermic change
5. Combining magnesium metal with hydrochloric acid produces a:
a. Physical and exothermic change
b. Physical and endothermic change
c. Chemical and exothermic change
d. Chemical and endothermic change
6. What type of change occurs when citric acid is mixed with baking soda?
a. Physical and exothermic change
b. Physical and endothermic change
c. Chemical and exothermic change
d. Chemical and endothermic change
Answers
1. B
2. C
3. C
4. B
5. C
6. D
Summary
36
Once the students have completed the lab and obtained their results, it would be a good time to revisit
the original clicker prediction questions for the lab. Revisiting the questions gives the students the
opportunity to answer the same questions, but this time, with the knowledge that they gained during
the experiment. It also gives them the chance to review key terms and ask about the rationale behind
the correct answers. The next activity will allow the teacher to formatively assess the students’
understanding as the students answer “first response” questions about changes in matter. Students
should be given a chance to have a copy of the questions ahead of time so that they can research the
answers prior to the first response game.
Post-Instruction Clicker Activities
Introduction
For this clicker activity, students will play a first response game to review the Changes in Matter
Concept. Students will experience a high level of engagement, as they work individually or in groups, to
complete a formative assessment on the identification of various reactions as physical or chemical, and
as exothermic or endothermic. They will also be expected to answer concept questions about physical
and chemical changes, phase changes, energy, and energy changes during physical and chemical
changes.
Questions
1. A change that involves the mixing of two or more chemicals, refers to a:
a. Chemical change
b. Physical change
c. Phase change
d. Not enough information
2. During a ___________ _________ there is a chemical reaction, a new substance is formed and
energy is either given off or absorbed.
a. Physical change
b. Chemical change
c. Phase change
d. Endothermic change
3. A __________ ________ in a substance doesn’t change what the substance is.
a. Physical change
b. Chemical change
c. Phase change
d. Exothermic change
4. A phase change happens when:
a. a sample of matter changes from one state (solid, liquid or gas) to another while also
producing a change in chemical composition.
b. a sample of matter changes from one state (solid, liquid or gas) to another without
producing a change in chemical composition.
5. A chemical reaction is:
37
6.
7.
8.
9.
10.
11.
12.
13.
38
a. A change in which a substance (or substances) is changed into one or more new
substances
b. A change in which a substance (or substances) undergoes a phase change
c. A change that must involve combustion
d. A change that occurs when matter is exposed to temperatures below absolute zero
Energy refers to:
a. The rate at which work is done
b. The ability to do work
c. A measure of the intensity of heat
d. Force per unit area
During an exothermic reaction:
a. Heat does not flow in or out of the system
b. Heat exits the system
c. Heat enters the system
d. Heat is intense
During an endothermic reaction:
a. Heat does not flow in or out of the system
b. Heat exits the system
c. Heat enters the system
d. Heat is intense
Melting ice cubes is a:
a. Physical and exothermic change
b. Physical and endothermic change
c. Chemical and exothermic change
d. Chemical and endothermic change
Burning a candle is a:
a. Physical and exothermic change
b. Physical and endothermic change
c. Chemical and exothermic change
d. Chemical and endothermic change
Rusting steel wool (by adding steel wool to bleach and hydrogen peroxide) is a:
a. Physical and exothermic change
b. Physical and endothermic change
c. Chemical and exothermic change
d. Chemical and endothermic change
Mixing water and potassium chloride (a type of salt) produces a:
a. Physical and exothermic change
b. Physical and endothermic change
c. Chemical and exothermic change
d. Chemical and endothermic change
Combining magnesium metal with hydrochloric acid produces a:
a. Physical and exothermic change
b. Physical and endothermic change
c. Chemical and exothermic change
d. Chemical and endothermic change
14. What type of change occurs when citric acid is mixed with baking soda?
a. Physical and exothermic change
b. Physical and endothermic change
c. Chemical and exothermic change
d. Chemical and endothermic change
Answers
1. D
2. B
3. A
4. B
5. A
6. B
7. B
8. C
9. B
10. C
11. C
12. B
13. C
14. D
Summary
Having finished the first response game on changes in matter, students are now ready to complete a
formative assessment on matter and its changes. Topics will include the properties of matter, the
classification of matter and the changes in matter.
Summative Assessment – Matter & Its Changes
Introduction
The summative assessment on Matter & Its Changes consists of the post-instruction questions found in
this unit for the properties of matter, the classification of matter and the changes in matter. The
assessment can be used in addition to, or in place of, a written assessment for the concepts found in
unit two. It will include questions selected from previous unit two clicker activities and must be
completed individually. To prepare for the assessment, students should study their notes and any
worksheets that were handed out for unit two.
Questions
1. Which of the following best defines the word “chemistry”?
a. The science of the composition, structure, properties, and reactions of matter,
especially of atomic and molecular systems
b. The study of the natural or material world and phenomena; natural philosophy
39
2.
3.
4.
5.
6.
7.
40
c. The science of life and of living organisms, including their structure, function, growth,
origin, evolution, and distribution. It includes botany and zoology and all their
subdivisions
d. The scientific study of the origin, history, and structure of the earth
A substance is:
a. A composition of two or more substances that are not chemically combined with each
other and are capable of being separated
b. A pure, macroscopically homogeneous substance consisting of atoms or ions of two or
more different elements in definite proportions that cannot be separated by physical
means
c. A specific type of matter, especially a homogeneous material with a definite
composition
d. A system in which finely divided particles, which are approximately 10 to 10,000
angstroms in size, are dispersed within a continuous medium in a manner that prevents
them from being filtered easily or settled rapidly
A chemical property is best defined as:
a. a basic or essential attribute shared by all members of a class; "a study of the physical
properties of atomic particles"
b. a property used to characterize materials in reactions that change their identity
c. any property used to characterize matter and energy and their interactions
d. the degree of hotness or coldness of a body or environment (corresponding to its
molecular activity)
A physical property is best defined as:
a. a basic or essential attribute shared by all members of a class; "a study of the physical
properties of atomic particles"
b. a property used to characterize materials in reactions that change their identity
c. any property used to characterize matter and energy and their interactions
d. the degree of hotness or coldness of a body or environment (corresponding to its
molecular activity)
An intensive property of matter is:
a. A property that depends on the amount of matter present
b. A property that does not depend on the amount of matter present
c. A measurement of the gravitational force of attraction of the earth acting on an object
d. A measurement of the amount of space a substance occupies
An extensive property of matter is:
a. A property that depends on the amount of matter present
b. A property that does not depend on the amount of matter present
c. A measurement of the gravitational force of attraction of the earth acting on an object
d. A measurement of the amount of space a substance occupies
Density is:
a. The amount of three dimensional space that any solid, liquid or gas object occupies
b. The amount of matter that an object contains
8.
9.
10.
11.
12.
13.
14.
15.
16.
41
c. The amount of matter contained in a given amount of space
d. The upward force on an object produced by the surrounding liquid or gas in which it is
fully or partially immersed, due to the pressure difference of the fluid between the top
and bottom of the object
Mass is:
a. The amount of three dimensional space that any solid, liquid or gas object occupies
b. The amount of matter that an object contains
c. The amount of matter contained in a given amount of space
d. The upward force on an object produced by the surrounding liquid or gas in which it is
fully or partially immersed, due to the pressure difference of the fluid between the top
and bottom of the object
Volume is:
a. The amount of three dimensional space that any solid, liquid or gas object occupies
b. The amount of matter that an object contains
c. The amount of matter contained in a given amount of space
d. The upward force on an object produced by the surrounding liquid or gas in which it is
fully or partially immersed, due to the pressure difference of the fluid between the top
and bottom of the object
The element carbon is a good example of a:
a. Pure substance
b. Mixture
The compound CO2 is a good example of a:
a. Pure substance
b. Mixture
Mixtures can be:
a. Either homogeneous or heterogeneous
b. Either homozygous or heterozygous
c. Composed of only one type of element
d. Composed of only one type of compound
True or False: Mixtures can be solutions
a. True
b. False
Three examples of different types of mixtures that are based upon the size of the solute are:
a. Suspension, colloidal and solution
b. Suspension, heterogeneous and solution
c. Suspension, homogeneous and solution
d. Both b and c
True or False: Homogeneous mixtures are also known as solutions
a. True
b. False
A good example of a suspension mixture is a bottle of:
a. Sugar water
b. Oil and water
17.
18.
19.
20.
21.
22.
23.
24.
42
c. Milk
d. Food coloring and water
A good example of a colloidal mixture is a container of:
a. Hair spray
b. Smoke
c. Whipped cream
d. Blood
e. All of the above
A good example of a solution is:
a. Oxygen in water
b. Salt in water
c. Marbles in water
d. Both a and b
You can separate a simple mixture by:
a. Physical means
b. Chemical means only
c. Adding a water softener
d. Heating the solution over an open flame
When you add material to a gas or liquid, the material you add is called the _________ and the
material you are adding to is called the __________.
a. solvent, solute
b. solute, solvent
c. mixing agent, dissolving agent
d. dissolving agent, mixing agent
A change that involves the mixing of two or more chemicals, refers to a:
a. Chemical change
b. Physical change
c. Phase change
d. Not enough information
During a ___________ _________ there is a chemical reaction, a new substance is formed and
energy is either given off or absorbed.
a. Physical change
b. Chemical change
c. Phase change
d. Endothermic change
A __________ ________ in a substance doesn’t change what the substance is.
a. Physical change
b. Chemical change
c. Phase change
d. Exothermic change
A phase change happens when:
a. a sample of matter changes from one state (solid, liquid or gas) to another while also
producing a change in chemical composition.
b. a sample of matter changes from one state (solid, liquid or gas) to another without
producing a change in chemical composition.
25. A chemical reaction is:
a. A change in which a substance (or substances) is changed into one or more new
substances
b. A change in which a substance (or substances) undergoes a phase change
c. A change that must involve combustion
d. A change that occurs when matter is exposed to temperatures below absolute zero
26. Energy refers to:
a. The rate at which work is done
b. The ability to do work
c. A measure of the intensity of heat
d. Force per unit area
27. During an exothermic reaction:
a. Heat does not flow in or out of the system
b. Heat exits the system
c. Heat enters the system
d. Heat is intense
28. During an endothermic reaction:
a. Heat does not flow in or out of the system
b. Heat exits the system
c. Heat enters the system
d. Heat is intense
29. Melting ice cubes is a:
a. Physical and exothermic change
b. Physical and endothermic change
c. Chemical and exothermic change
d. Chemical and endothermic change
30. Burning a candle is a:
a. Physical and exothermic change
b. Physical and endothermic change
c. Chemical and exothermic change
d. Chemical and endothermic change
31. Rusting steel wool (by adding steel wool to bleach and hydrogen peroxide) is a:
a. Physical and exothermic change
b. Physical and endothermic change
c. Chemical and exothermic change
d. Chemical and endothermic change
32. Mixing water and potassium chloride (a type of salt) produces a:
a. Physical and exothermic change
b. Physical and endothermic change
c. Chemical and exothermic change
d. Chemical and endothermic change
33. Combining magnesium metal with hydrochloric acid produces a:
a. Physical and exothermic change
b. Physical and endothermic change
c. Chemical and exothermic change
43
d. Chemical and endothermic change
34. What type of change occurs when citric acid is mixed with baking soda?
a. Physical and exothermic change
b. Physical and endothermic change
c. Chemical and exothermic change
d. Chemical and endothermic change
Answers
1. A
2. C
3. B
4. C
5. B
6. A
7. C
8. B
9. A
10. A
11. A
12. A
13. A
14. A
15. A
16. B
17. E
18. D
19. A
20. B
21. D
22. B
23. A
24. B
25. A
26. B
27. B
28. C
29. B
30. C
31. C
32. B
33. C
34. D
Summary
44
Students have now successfully completed all of the questions for unit two, Matter & Its Changes. They
learned how chemistry can be used to explain how matter is described, how it is classified and the types
of changes that it undergoes. In the next unit, students will be learning about how the theory of the
atom has changed over time.
Unit Three: Atoms
Concept: History of Atomic Theory
Pre-Instruction Clicker Activities
Introduction
First, students will read a handout about how various scientists have contributed to The Modern Atomic
Theory. Next, students will either work alone or as part of a group to answer vocabulary questions
about the scientists. Students should be allowed to use the handout while answering the clicker
questions due to the fact that there are several contributing scientists and because the information is
new.
Questions
1. Who discovered the existence of tiny negative particles called electrons?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
2. Who said that electrons orbit the nucleus in “shells”?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
3. Who came up with the idea that matter could NOT be divided indefinitely?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
4. Who came up with the “plum pudding” model that illustrated how negative electrons existed
within a positive framework?
45
5.
6.
7.
8.
9.
10.
46
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
The idea that matter consisted of four “elements” belonged to:
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
The idea that matter consists of mostly empty space originated with:
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
Who compared atoms to billiard balls, stating that they were solid and indivisible?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
Which scientist said that electrons can be bumped up to a higher shell if hit by an electron or a
photon of light?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
Who came up with the ideas that atoms of different elements combine in constant ratios to
form compounds and that atoms are rearranged in reactions?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
Who discovered that atoms have a positive nucleus that makes up most of an atom’s mass?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
11. Who came up with the ideas that all matter is made of atoms and that atoms of an element are
identical?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
Answers
1. D
2. F
3. A
4. D
5. B
6. E
7. C
8. F
9. C
10. E
11. C
Summary
Now that students have been exposed to many of the scientists that have contributed to The Modern
Atomic Theory, they are ready to learn the details behind each scientist’s contributions to the theory.
They will be presented with an explanation as to how each of the scientists came up with their idea
and/or discovery about the atom. During this process they will look at labeled diagrams of some of the
equipment that the scientists used as a means of illustrating how the theory of the atom has changed
over time due to technological developments.
Clicker Activities for Instruction
Introduction
During this activity, students will answer embedded questions about how the theory of the atom has
changed over time due to technological developments. The questions are designed to increase student
engagement as they apply what they are learning about how scientists have contributed to The Modern
Atomic Theory. Questions can be answered individually or in groups.
Questions
1. Democritus wondered if matter could be divided into smaller and smaller pieces forever, or if
there was a limit to the number of times a piece of matter could be divided. Which of the
following statements seems to best answer his question:
a. Matter can be divided an infinite number of times.
b. There is a limit to the number of times that matter can be divided.
c. Matter can only be divided by a nuclear explosion.
d. Only mixtures can be divided because pure matter is indivisible.
47
2. Why was Aristotle and Plato’s “4 Elements” theory so well respected, even though it was totally
wrong?
a. Because empirical evidence favored the “4 Elements” theory
b. They were the eminent philosophers of the time, and people believed whatever they
said
3. Dalton’s Atomic Theory, also known as one of the foundations of modern chemistry, states that:
a. All elements are composed of indivisible and indestructible particles called atoms.
b. Atoms of the same element are exactly alike.
c. Atoms of different elements are different.
d. Compounds are formed by the joining of atoms of two or more elements.
e. All of the above
4. J.J. Thomson used the cathode ray tube to:
a. Show that matter contains positively charged particles called protons
b. Show that matter contains negatively charged particles called electrons
c. Show that matter contains neutrally charged particles called neutrons
5. Rutherford’s Gold Foil experiment showed that matter:
a. Resembled the “plum pudding” model that J.J. Thomson had proposed
b. Lacked a nucleus
c. Has a large nucleus compared to the atom as a whole
d. Was composed of atoms that contained mostly empty space with the exception of
small, dense, positively charged particles found in what he called a “nucleus”
6. Niels Bohr proposed that:
a. Electrons move around the nucleus of an atom in a specific path, much like the planets
orbit around the sun
b. According to the theory of wave mechanics, electrons do not move about an atom in a
definite path, like the planets around the sun
Answers
1. B
2. B
3. E
4. B
5. D
6. A
Summary
The students have now been taught about each of the major contributors to today’s Modern Atomic
Theory. They also learned about how the theory changed over time due to technological developments.
It is recommended that the students either create, or are given, a graphic organizer that illustrates the
scientists and their contributions. Next, students are ready to take a post-instruction clicker quiz on the
scientists, this time without using their notes.
Post-Instruction Clicker Activities
Introduction
Here, students will be given the same vocabulary questions that they were given for the pre-instruction
questions on The History of Atomic Theory. This time, however, they will not be allowed to use notes.
The questions should be distributed ahead of time so that students are given the opportunity to study.
48
Questions can either be answered individually or in groups and the questions can also be answered with
a set time limit or as a first response game.
1. Who discovered the existence of tiny negative particles called electrons?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
2. Who said that electrons orbit the nucleus in “shells”?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
3. Who came up with the idea that matter could NOT be divided indefinitely?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
4. Who came up with the “plum pudding” model that illustrated how negative electrons existed
within a positive framework?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
5. The idea that matter consisted of four “elements” belonged to:
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
6. The idea that matter consists of mostly empty space originated with:
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
7. Who compared atoms to billiard balls, stating that they were solid and indivisible?
a. Democritus
49
8.
9.
10.
11.
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
Which scientist said that electrons can be bumped up to a higher shell if hit by an electron or a
photon of light?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
Who came up with the ideas that atoms of different elements combine in constant ratios to
form compounds and that atoms are rearranged in reactions?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
Who discovered that atoms have a positive nucleus that makes up most of an atom’s mass?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
Who came up with the ideas that all matter is made of atoms and that atoms of an element are
identical?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
Answers
1. D
2. F
3. A
4. D
5. B
6. E
7. C
8. F
9. C
10. E
50
11. C
Concept: Structure of the Atom
Pre-Instruction Clicker Activities
Introduction
Due to the fact that students have most likely been taught about the structure of the atom prior to
taking high school chemistry, the teacher will administer a pre-test clicker activity to check prior
knowledge. The questions focus on the particles that make-up and atom and where they are found
within the atom’s structure. They also focus on the electrical charges for these particles and how the
periodic table is used to determine the numbers and types of particles found within an atom of a
particular element. Students should work individually to complete this activity.
Questions
1. An element’s atomic number stands for:
a. The number of protons, neutrons, or electrons
b. The number of protons or electrons
c. The number of protons plus neutrons
d. The number of protons only
e. The number of electrons only
f. The number of neutrons only
2. An element’s mass number stands for:
a. The number of protons, neutrons, or electrons
b. The number of protons or electrons
c. The number of protons plus neutrons
d. The number of protons only
e. The number of electrons only
f. The number of neutrons only
3. To determine how many protons an atom has, one must:
a. Subtract the element’s mass number from its atomic number
b. Subtract the element’s atomic number from its mass number
c. Use the element’s atomic number
d. Use the element’s mass number
4. To determine how many neutrons an atom has, one must:
a. Subtract the element’s mass number from its atomic number
b. Subtract the element’s atomic number from its mass number
c. Use the element’s atomic number
d. Use the element’s mass number
5. To determine how many electrons an atom has, one must:
a. Subtract the element’s mass number from its atomic number
b. Subtract the element’s atomic number from its mass number
c. Use the element’s atomic number
d. Use the element’s mass number
6. Protons are:
a. Positive
51
7.
8.
9.
10.
11.
12.
13.
14.
52
b. Negative
c. Neutral
d. Polar, with a slightly positive region and a slightly negative region
Neutrons are:
a. Positive
b. Negative
c. Neutral
d. Polar, with a slightly positive region and a slightly negative region
Electrons are:
a. Positive
b. Negative
c. Neutral
d. Polar, with a slightly positive region and a slightly negative region
Positively charged atoms are positive because:
a. They have lost one or more electrons
b. They have gained one or more electrons
c. They have lost one or more protons
d. They have gained one or more protons
Negatively charged atoms are negative because:
a. They have lost one or more electrons
b. They have gained one or more electrons
c. They have lost one or more protons
d. They have gained one or more protons
Atoms with a negative charge are called:
a. Electrons
b. Protons
c. Cations
d. Anions
e. Quarks
f. Leptons
Atoms with a positive charge are called:
a. Electrons
b. Protons
c. Cations
d. Anions
e. Quarks
f. Leptons
Atoms that are not neutral, but have a positive or negative charge are considered to be:
a. Cations
b. Anions
c. Ions
d. Isotopes
Isotopes are atoms:
a. Of different elements that have the same number of protons and the same number of
neutrons
b. Of the same element that have the same number of protons and the same number of
neutrons
c. Of the same element that have the same number of protons but a different number of
neutrons
d. Of the same element that have different atomic weights
e. Both b and d
f. Both c and d
15. Which subatomic particles are located in the nucleus of an atom?
a. Protons
b. Neutrons
c. Electrons
d. Both a, b and c
e. Both a and b
f. Both a and c
16. Which subatomic particles are located in energy levels that surround the nucleus?
a. Protons
b. Neutrons
c. Electrons
d. Both a, b and c
e. Both a and b
f. Both a and c
Answers
1. B
2. C
3. C
4. B
5. C
6. A
7. C
8. B
9. A
10. B
11. D
12. C
13. C
14. F
15. E
16. C
Summary
Once the students have finished the pre-instruction quiz the teacher will have an idea as to what the
students already know about atomic structure. If the students did well, the teacher can move quickly
through the review and have the students begin practicing the application of the concepts. However, if
they did not do well, the teacher should spend an adequate amount of time teaching the concepts so
that they are able to develop a solid understanding of atomic structure before they move on to the next
concept entitled, “Electrons and Their Arrangement.”
Clicker Activities for Instruction
53
Introduction
For this activity students will answer embedded concept questions during lessons on atomic structure.
Students can work alone or in groups to utilize peer instruction as they answer the questions. They will
use new definitions and examples, along with a periodic table to answer specific questions about the
composition, structure and characteristics of different atoms.
Questions
1. The overall charge on the nucleus of an atom is positive.
a. True
b. False
2. Electrons are almost as heavy as protons.
a. True
b. False
3. Where do protons, neutrons and electrons live?
a. Protons and neutrons live in a cloud while electrons reside in the nucleus
b. Protons and electrons live in a cloud while neutrons reside in the nucleus
c. Electrons live in a cloud while protons and neutrons reside in the nucleus
d. Neutrons live in a cloud while protons and electrons reside in the nucleus
4. In a neutral atom, the number of protons is equal to the number of electrons.
a. True
b. False
5. If 30 protons are present in an atom, how many electrons are needed to balance out the
charge?
a. 15
b. 0
c. 30
d. 60
6. If sodium has 23 protons, what is its atomic number?
a. 46
b. 22
c. 21
d. 23
7. If the mass number for Argon is 40, how many neutrons does one atom of Argon have?
a. 40
b. 80
c. 22
d. 20
8. If Phosphorous has an atomic number of 15, how many electrons does it have?
a. 15
b. 30
c. 7.5
d. 60
9. The first through fourth rings of electron energy levels can hold how many electrons?
a. 3, 9, 19 and 33
b. 2, 8, 18 and 33
c. 32, 18, 8 and 2
d. 2, 8, 18 and 32
10. Atoms or groups of atoms with a positive or negative charge are considered to be:
54
11.
12.
13.
14.
a. Isotopes
b. Radioactive
c. Ions
d. Leptons
If Calcium loses 2 electrons, what type of ion does it form and why?
a. It just becomes and ion because ions are charged particles
b. It becomes a cation because cations are positive. When Calcium loses 2 negatives the
overall atom is left with a charge of positive 2
c. It becomes an anion because anions are positive. When Calcium loses 2 negatives the
overall atom is left with a charge of positive 2
d. It becomes an anion because anions are negative. When Calcium loses 2 negatives the
overall atom is left with a charge of negative 2
Which of the following statements is generally true?
a. Metals gain electrons to form cations
b. Nonmetals gain electrons to form cations
c. Metals lose electrons to form cations
d. Nonmetals gain electrons to form anions
e. Both a and b
f. Both c and d
Boron-10 and Boron-12 are examples of:
a. Ions
b. Cations
c. Anions
d. Isotopes
Why does the periodic table list average atomic mass numbers for each of the elements?
a. Due to the existence of ions, the charges are constantly changing
b. Because of the existence of ions, the mass of a collection of atoms has an average value
c. Because of the existence of isotopes, the mass of a collection of molecules has an
average value
d. Because of the existence of isotopes, the mass of a collection of atoms has an average
value
Answers
1. A
2. B
3. C
4. A
5. C
6. D
7. C
8. A
9. D
10. C
11. B
12. F
13. D
14. D
55
Summary
After this activity, students will have learned about the structure of the atom, how to use the periodic
table to determine its characteristics, and how to differentiate between ions and isotopes. To prepare
for the next activity, students should do two things. First, they should practice using the periodic table
to answer additional questions about atomic structure in class and for homework. Second, they should
be given the questions to the post-instruction clicker activities so that they can be prepared for the
upcoming first-response game on atomic structure.
Post-Instruction Clicker Activities
Introduction
For this activity, students will complete a formative assessment by answering first-response clicker
questions about atomic structure. Although students can answer questions individually or in groups,
students are likely to be more engaged if they work in teams to answer these questions. To ensure
individual participation within the group setting, students should be responsible to turn-in some sort of
written documentation for each of the questions. During the game, students will be determining the
number of subatomic particles in given atoms/isotopes/ions in addition to calculating the atomic mass
of an element given the fractional abundance of the element’s isotopes.
Questions
1. Which of the following represents the atomic number for Oxygen?
a. 8
b. 15.9994
c. 16
d. 2,6
2. How many protons are found in one atom of the element Oxygen?
a. 8
b. 15.9994
c. 16
d. 2,6
3. How many neutrons are found in one atom of the element Oxygen?
a. 8
b. 15.9994
c. 16
d. 2,6
4. How many electrons are found in one atom of the element Oxygen?
a. 8
b. 15.9994
c. 16
d. 2,6
5. How many neutrons are found in Boron-12?
a. 5
b. 10.811
c. 11
d. 7
6. How many neutrons are found in Carbon-14?
a. 6
b. 12.0107
56
7.
8.
9.
10.
11.
12.
13.
14.
15.
57
c. 8
d. 12
Isotopes of the same element differ according to their number of:
a. Electrons
b. Protons
c. Neutrons
d. Subatomic particles
The periodic table lists average atomic mass numbers for the elements because:
a. Of the existence of ions
b. Of the existence of isotopes
c. Radioactive isotopes are constantly decaying
d. It is impossible to find the total mass for all of the elements
The mass number for Sulfur (S), rounded to the nearest whole number is:
a. 16
b. 15.9994
c. 33
d. 32.065
e. 32
What would the average atomic mass for Silicon be given the following mass percentages:
Si-28 = 92.23%, Si-29 = 4.67%, Si-30 = 3.10%?
a. 100
b. 28.1087
c. 28.0855
d. 28
Ions only form when:
a. Atoms gain positive protons
b. Atoms lose positive protons
c. Atoms gain negative electrons
d. Atoms lose negative electrons
e. Both a and b
f. Both c and d
Metals tend to form:
a. Cations
b. Anions
c. Isotopes
d. Stable compounds
Nonmetals tend to form:
a. Cations
b. Anions
c. Isotopes
d. Stable compounds
(Mg2+) has:
a. Lost two electrons
b. Gained two electrons
c. Lost two protons
d. Gained two protons
(F-) has:
a. Lost one electron
b. Gained one electron
c. Lost one proton
d. Gained one proton
16. Using the following mass percentages, calculate the average atomic mass for Lithium:
Li-6 = 7.0%, Li-7 = 92.5%, Li-8 = 0.5%
a. 3
b. 6.941
c. 7
d. 7.295
Answers
1. A
2. A
3. A
4. A
5. D
6. C
7. C
8. B
9. E
10. B
11. F
12. A
13. B
14. A
15. B
16. D
Summary
For this activity, students displayed their ability to determine the number of subatomic particles in given
atoms/isotopes/ions in addition to being able to calculate the atomic mass of an element given the
fractional abundance of the element’s isotopes. Next, students will be learning about electrons and
how they are arranged within an atom. This topic is also referred to as “electron configuration.”
Concept: Electrons and Their Arrangement
Pre-Instruction Clicker Activities
Introduction
Prior to answering the pre-instruction questions for this section, students must be introduced to s,p,d
and f energy levels. The best way for students to learn these levels is for them to see where they are
located on the periodic table. After they learn how to recognize an atom’s highest occupied energy level
as either s,p,d or f by using the periodic table, they will answer clicker questions to illustrate their
understanding. Questions can either be answered individually or in groups.
Questions
58
1. Hydrogen’s highest occupied energy level is:
a. 1s^1
b. 2s^1
c. 1p^1
d. 2p^1
2. Lithium’s highest occupied energy level is:
a. 1s^1
b. 1s^2
c. 2s^1
d. 3s^1
3. Boron’s highest occupied energy level is:
a. 1s^1
b. 2s^1
c. 2p^1
d. 2p^2
4. Neon’s highest occupied energy level is:
a. 1p^6
b. 2p^6
c. 3p^6
d. 2p^5
5. Sodium’s highest occupied energy level is:
a. 2p^1
b. 2p^6
c. 3s^2
d. 3s^1
6. Aluminum’s highest occupied energy level is:
a. 3s^2
b. 4s^2
c. 3p^1
d. 3p^3
7. Sulfur’s highest occupied energy level is:
a. 3p^1
b. 3p^2
c. 3p^3
d. 3p^4
8. Argon’s highest occupied energy level is:
a. 2p^6
b. 3p^6
c. 1s^6
d. 3s^6
9. Zinc’s highest occupied energy level is:
a. 4s^2
b. 3s^2
c. 3d^10
d. 4d^10
10. Gold’s highest occupied energy level is:
a. 5d^10
b. 6s^1
59
c. 7s^1
d. 4f^14
Answers
1. A
2. C
3. C
4. B
5. D
6. C
7. D
8. B
9. C
10. A
Summary
Now that students are familiar with how to use the periodic table to determine an element’s highest
occupied energy level, they are ready to begin learning about how to determine an element’s complete
electron configuration. In the next section, they will learn how to do this while answering clicker
questions along the way!
Clicker Activities for Instruction
Introduction
Before students begin the next activity, they must understand what an atom’s ground state is and how
to predict an atom’s ground state electron configuration. After the teacher models how to predict an
atom’s ground state electron configuration, the students will be able to predict electron configurations
for the elements in the next activity. Questions can be answered individually or in groups.
Questions
1. The ground state electron configuration for hydrogen is:
a. 1s^1
b. 1s^2
c. 1s^3
d. 1s^4
2. The ground state electron configuration for lithium is:
a. 2s^2
b. [He]2s^1
c. [Ne]3s^1
d. [He]2s^2
3. The ground state electron configuration for nitrogen is:
a. 2s^2
b. [He]2s^1
c. [Ne]3s^1
d. [He]2s^2, 2p^3
4. The ground state electron configuration for magnesium is:
a. [He]2s^2, 2p^3
b. [Ne]3s^2
60
5.
6.
7.
8.
9.
10.
11.
12.
c. [He]2s^2, 2p^3
d. [Ne]2s^2, 2p^3
The ground state electron configuration for chlorine is:
a. [Ne]3s^2, 3p^5
b. [Ne]3s^2, 3p^4
c. [He]3s^2, 3p^5
d. [Ne]3s^2
The ground state electron configuration for potassium is:
a. 2s^1
b. [He]2s^1
c. [Ne]3s^1
d. [Ar]4s^1
The ground state electron configuration for iron is:
a. [Ne]3d^6, 4s^2
b. [Ar]3d^5, 4s^1
c. [Ar]3d^6, 4s^2
d. [Ar]3d^6, 4s^1
The ground state electron configuration for zinc is:
a. [Ne]3d^6, 4s^2
b. [Ne]3d^10, 4s^1
c. [Ar]3d^1, 4s^2
d. [Ar]3d^10, 4s^2
[Ar]3d^5,4s^2 is the ground state electron configuration for which of the following elements?
a. Mg
b. Mn
c. Ni
d. Au
[Ne]3s^2 is the ground state electron configuration for which of the following elements?
a. Mg
b. Mn
c. Ni
d. Au
[He]2s^2,2p^6 is the ground state electron configuration for which of the following elements?
a. Ar
b. Kr
c. F
d. Ne
[He]2s^2 is the ground state electron configuration for which of the following elements?
a. He
b. Li
c. Be
d. B
Answers
1. A
2. B
3. D
4. B
61
5.
6.
7.
8.
9.
10.
11.
12.
A
D
C
D
B
A
D
C
Summary
Now that students have learned how to determine an atom’s ground state electron configuration, they
are ready look at electron configuration in a little more depth. For example, in the next section students
will answer conceptual questions about electron configuration, demonstrate their understanding of
orbital notation and identify Lewis dot diagrams for particular elements.
Post-Instruction Clicker Activities
Introduction
Here, students will answer concept questions as they complete a formative assessment to demonstrate
their knowledge about electrons and their arrangement. Working individually, they will answer
questions about the ground state arrangement of electrons around an atom, orbital notation and Lewis
dot structures using the principles and rules that they have learned. These questions are designed to
not only show if students can write information about an atom’s electron configuration, but also to
show if they can explain they why behind some of the principles that explain electron theory.
Questions
1. How many principle energy levels are there?
a. 4
b. 5
c. 6
d. 7
2. What are the names of the sublevels?
a. Proton, neutron and electron
b. Lepton, quark, and positron
c. r, s, t, u
d. s, p, d, f
3. How many orbitals can there be in each sublevel?
a. s = 1, p = 3, d = 5, f = 7
b. s = 2, p = 6, d = 10, f = 14
c. s = 11, p = 32, d = 53, f = 74
d. s = 1, p = 3, d = 5, f = 17
4. How many electrons can fit into full s, p, d, and f sublevels respectively? (2,6,10,14)
a. 2, 5, 9, 13
b. 1, 3, 5, 7
c. 2, 6, 10, 14
d. 20, 60, 100, 140
5. “When electrons fill orbitals of the same energy, they prefer to enter empty orbitals first, and all
electrons in half-filled orbitals have the same spin,” refers to which of the following:
62
6.
7.
8.
9.
10.
11.
12.
13.
63
a. Hund’s Rule
b. The Pauli Exclusion Principle
c. The Law of Conservation of Mass
d. The Theory of Relativity
“No more than two electrons can occupy the same orbital and they can only do this if they have
the opposite spin,” refers to which of the following:
a. Hund’s Rule
b. The Pauli Exclusion Principle
c. The Law of Conservation of Mass
d. The Theory of Relativity
How many electrons can fit on a single orbital?
a. 1
b. 1.5
c. 2
d. 2.5
e. 8
What are the electrons called that are represented by small dots that are placed around an
element’s chemical symbol?
a. Variable spin electrons
b. Constant velocity electrons
c. Electromagnetic electrons
d. Valence electrons
How many dots would be placed around the capital letter “H” when drawing hydrogen’s Lewis
structure?
a. 1
b. 3
c. 5
d. 8
How many dots would be placed around the symbol for Aluminum when drawing aluminum’s
Lewis structure?
a. 1
b. 3
c. 5
d. 8
How many dots would be placed around the symbol for Krypton when drawing Krypton’s Lewis
structure?
a. 1
b. 3
c. 5
d. 8
The ground state electron configuration for iron is:
a. [Ne]3d^6, 4s^2
b. [Ar]3d^5, 4s^1
c. [Ar]3d^6, 4s^2
d. [Ar]3d^6, 4s^1
The ground state electron configuration for zinc is:
a. [Ne]3d^6, 4s^2
b. [Ne]3d^10, 4s^1
c. [Ar]3d^1, 4s^2
d. [Ar]3d^10, 4s^2
14. [Ar]3d^5,4s^2 is the ground state electron configuration for which of the following elements?
a. Mg
b. Mn
c. Ni
d. Au
15. [Ne]3s^2 is the ground state electron configuration for which of the following elements?
a. Mg
b. Mn
c. Ni
d. Au
16. [He]2s^2,2p^6 is the ground state electron configuration for which of the following elements?
a. Ar
b. Kr
c. F
d. Ne
Answers
1. D
2. D
3. A
4. C
5. A
6. B
7. C
8. D
9. A
10. B
11. D
12. C
13. D
14. B
15. A
16. D
Summary
If students had trouble with the previous formative assessment, the teacher should go back and reteach the Electrons and Their Arrangement concept before moving on to the summative assessment for
this unit. If this is the case, the previous assessment can be given again in normal quiz mode or as a first
response game if it seems that the students need some added incentive due to the fact that they will be
repeating the same activity.
Summative Assessment - Atoms
Introduction
64
The summative assessment on Atoms consists of the post-instruction questions found in this unit for the
History of Atomic Theory, Structure of Atoms and Electrons and Their Arrangement. The assessment can
be used in addition to, or in place of, a written assessment for the concepts found in unit three. It will
include questions selected from previous unit three clicker activities and must be completed
individually. To prepare for the assessment, students should study their notes and any worksheets that
were handed out for unit three.
Questions
1. Who discovered the existence of tiny negative particles called electrons?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
2. Who said that electrons orbit the nucleus in “shells”?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
3. Who came up with the idea that matter could NOT be divided indefinitely?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
4. Who came up with the “plum pudding” model that illustrated how negative electrons existed
within a positive framework?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
5. The idea that matter consisted of four “elements” belonged to:
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
6. The idea that matter consists of mostly empty space originated with:
a. Democritus
b. Aristotle
c. Dalton
65
7.
8.
9.
10.
11.
12.
13.
66
d. Thomson
e. Rutherford
f. Bohr
Who compared atoms to billiard balls, stating that they were solid and indivisible?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
Which scientist said that electrons can be bumped up to a higher shell if hit by an electron or a
photon of light?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
Who came up with the ideas that atoms of different elements combine in constant ratios to
form compounds and that atoms are rearranged in reactions?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
Who discovered that atoms have a positive nucleus that makes up most of an atom’s mass?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
Who came up with the ideas that all matter is made of atoms and that atoms of an element are
identical?
a. Democritus
b. Aristotle
c. Dalton
d. Thomson
e. Rutherford
f. Bohr
Which of the following represents the atomic number for Oxygen?
a. 8
b. 15.9994
c. 16
d. 2,6
How many protons are found in one atom of the element Oxygen?
a. 8
14.
15.
16.
17.
18.
19.
20.
21.
22.
67
b. 15.9994
c. 16
d. 2,6
How many neutrons are found in one atom of the element Oxygen?
a. 8
b. 15.9994
c. 16
d. 2,6
How many electrons are found in one atom of the element Oxygen?
a. 8
b. 15.9994
c. 16
d. 2,6
How many neutrons are found in Boron-12?
a. 5
b. 10.811
c. 11
d. 7
How many neutrons are found in Carbon-14?
a. 6
b. 12.0107
c. 8
d. 12
Isotopes of the same element differ according to their number of:
a. Electrons
b. Protons
c. Neutrons
d. Subatomic particles
The periodic table lists average atomic mass numbers for the elements because:
a. Of the existence of ions
b. Of the existence of isotopes
c. Radioactive isotopes are constantly decaying
d. It is impossible to find the total mass for all of the elements
The mass number for Sulfur (S), rounded to the nearest whole number is:
a. 16
b. 15.9994
c. 33
d. 32.065
e. 32
What would the average atomic mass for Silicon be given the following mass percentages:
Si-28 = 92.23%, Si-29 = 4.67%, Si-30 = 3.10%?
a. 100
b. 28.1087
c. 28.0855
d. 28
Ions only form when:
a. Atoms gain positive protons
b. Atoms lose positive protons
23.
24.
25.
26.
27.
28.
29.
30.
31.
68
c. Atoms gain negative electrons
d. Atoms lose negative electrons
e. Both a and b
f. Both c and d
Metals tend to form:
a. Cations
b. Anions
c. Isotopes
d. Stable compounds
Nonmetals tend to form:
a. Cations
b. Anions
c. Isotopes
d. Stable compounds
(Mg2+) has:
a. Lost two electrons
b. Gained two electrons
c. Lost two protons
d. Gained two protons
(F-) has:
a. Lost one electron
b. Gained one electron
c. Lost one proton
d. Gained one proton
Using the following mass percentages, calculate the average atomic mass for Lithium:
Li-6 = 7.0%, Li-7 = 92.5%, Li-8 = 0.5%
a. 3
b. 6.941
c. 7
d. 7.295
How many principle energy levels are there?
a. 4
b. 5
c. 6
d. 7
What are the names of the sublevels?
a. Proton, neutron and electron
b. Lepton, quark, and positron
c. r, s, t, u
d. s, p, d, f
How many orbitals can there be in each sublevel?
a. s = 1, p = 3, d = 5, f = 7
b. s = 2, p = 6, d = 10, f = 14
c. s = 11, p = 32, d = 53, f = 74
d. s = 1, p = 3, d = 5, f = 17
How many electrons can fit into full s, p, d, and f sublevels respectively? (2,6,10,14)
a. 2, 5, 9, 13
b. 1, 3, 5, 7
32.
33.
34.
35.
36.
37.
38.
39.
69
c. 2, 6, 10, 14
d. 20, 60, 100, 140
“When electrons fill orbitals of the same energy, they prefer to enter empty orbitals first, and all
electrons in half-filled orbitals have the same spin,” refers to which of the following:
a. Hund’s Rule
b. The Pauli Exclusion Principle
c. The Law of Conservation of Mass
d. The Theory of Relativity
“No more than two electrons can occupy the same orbital and they can only do this if they have
the opposite spin,” refers to which of the following:
a. Hund’s Rule
b. The Pauli Exclusion Principle
c. The Law of Conservation of Mass
d. The Theory of Relativity
How many electrons can fit on a single orbital?
a. 1
b. 1.5
c. 2
d. 2.5
e. 8
What are the electrons called that are represented by small dots that are placed around an
element’s chemical symbol?
a. Variable spin electrons
b. Constant velocity electrons
c. Electromagnetic electrons
d. Valence electrons
How many dots would be placed around the capital letter “H” when drawing hydrogen’s Lewis
structure?
a. 1
b. 3
c. 5
d. 8
How many dots would be placed around the symbol for Aluminum when drawing aluminum’s
Lewis structure?
a. 1
b. 3
c. 5
d. 8
How many dots would be placed around the symbol for Krypton when drawing Krypton’s Lewis
structure?
a. 1
b. 3
c. 5
d. 8
The ground state electron configuration for iron is:
a. [Ne]3d^6, 4s^2
b. [Ar]3d^5, 4s^1
c. [Ar]3d^6, 4s^2
d. [Ar]3d^6, 4s^1
40. The ground state electron configuration for zinc is:
a. [Ne]3d^6, 4s^2
b. [Ne]3d^10, 4s^1
c. [Ar]3d^1, 4s^2
d. [Ar]3d^10, 4s^2
41. [Ar]3d^5,4s^2 is the ground state electron configuration for which of the following elements?
a. Mg
b. Mn
c. Ni
d. Au
42. [Ne]3s^2 is the ground state electron configuration for which of the following elements?
a. Mg
b. Mn
c. Ni
d. Au
43. [He]2s^2,2p^6 is the ground state electron configuration for which of the following elements?
a. Ar
b. Kr
c. F
d. Ne
Answers
1. D
2. F
3. A
4. D
5. B
6. E
7. C
8. F
9. C
10. E
11. C
12. A
13. A
14. A
15. A
16. D
17. C
18. C
19. B
20. E
21. B
22. F
23. A
24. B
25. A
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26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
41.
42.
43.
B
D
D
D
A
C
A
B
C
D
A
B
D
C
D
B
A
D
Summary
By now, students have covered the History of Atomic Theory, Structure of Atoms and Electrons and
Their Arrangement, all of the main concepts under the unit on Atoms. Next, students will begin to learn
about the History of the Periodic Table and Period Trends when they begin unit four on the Periodic
Table.
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