Student Textbook page 9
Answers to Making Connections Questions
1. Andrei Sakharov was called the “father of the Soviet hydrogen bomb” due to his work
in nuclear chemistry. He studied the effects of low-level radiation on people. He
became a notable champion of human rights, writing many articles that went on to
be published in western newspapers and journals. For his work on human rights
issues, he won the Nobel Peace Prize. However, this work was largely scorned in
Russia, and he was exiled by the Russian government.
Linus Pauling was the only person to win two Nobel Prizes. The first was for chemistry for his work on genetic influences in relation to the atomic structure of proteins
in hemoglobin. He discovered that sickle cell anemia is caused by genetic defect. The
second prize was the Nobel Peace Prize. He was instrumental in warning the public
about the biological danger of radioactive fallout from nuclear weapons testing.
Fang Lizhi is a Chinese astrophysicist and dissident who was charged by the Chinese
government for his role in the 1989 student rebellion in Tiananmen Square. In 1957
he was publicly rebuked and expelled from the Chinese Communist Party for a paper
he wrote decrying the Marxist position on physics and calling for a reform of the
educational system. He helped to establish a physics department at Peking’s
University of Science and Technology, and he continued his research on solid-state
and laser physics while teaching electromagnetism and quantum mechanics. In 1966
he was confined for a year and then sent to a communal farm to be “reeducated.”
During this period he was isolated from the scientific community, and he redirected
his field of study to cosmology. Released in 1969 to teach, Fang was forced to publish
his work under a pseudonym.
2. One example of a scientist who had to struggle to communicate his ideas to a scientific community unwilling to entertain them, initially, was Dmitri Mendeleev. At a
time when most scientists of note were European or North American, Mendeleev
experienced prejudice because he was Russian. Another example was Rachel Carson,
who was discriminated against because she was a woman.
Section Review Answers
Student Textbook page 10
1. Examples of student responses:
production of plastics for making juice bottles
production of textiles for making clothes
■ treatment and purification of drinking water
■ production of oxygen gas through photosynthesis
■ production of pharmaceuticals
■ food and beverage processing
2. Look for students to include a control in their experimental design. As well, the
concentration of detergent solution must be diluted, as noted in the question hint.
For example, students could have one jar with just pond water and algae (the
control), a second jar with pond water, algae, and very dilute detergent solution
(e.g., 1 drop in 50 mL of water), and a third jar with pond water, algae, and a less
dilute solution (e.g., 5 drops in 50 mL of water). All jars would be placed in sunlight.
■
■
Chapter 1 Observing Matter • MHR
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UNIT 1 Chapter 1 OBSERVING MATTER
3. Students may choose a table, a Venn diagram, or a mindmap to demonstrate the
connections among science, technology, society, and the environment.
Knowledge derived from science provides building blocks for technology.
Advances in technology can
aid in scientific endeavours.
4. (a)
(b)
(c)
(d)
technology
society
environment
science
1.2
Describing and Measuring Matter
Student Textbook pages 11–24
Describing Matter, page 11
Using Measurements to Describe Matter, page 14
Measurement and Uncertainty, pages 15–16
Significant Digits, Certainty, and Measurements, page 17
How Can You Tell Which Digits Are Significant?, pages 17–18
Accuracy and Precision, pages 18–19
Calculating with Significant Digits, page 20
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MHR • Unit 1 Matter and Chemical Bonding
Societal questions drive scientific inquiry.
The environment around us provides the impetus for scientific inquiry.
Society can help or hinder
environment.
ENVIRONMENT
Scientific research can lead to improvements for the environment.
SOCIETY
Environment allows for
society to exist.
Environmental issues drive technological achievements.
SCIENCE
Scientific knowledge
improves well-being of society.
Technological advances improve life.
Technological advancements can lead to less damage and more preservation of the environment.
Society needs drive technology.
TECHNOLOGY
Assessment and Evaluation
ThoughtLab/
ExpressLab/
Investigation
ExpressLab:
Significant Digits,
page 19
Curriculum
Expectations
Assessment
Tool/Technique
Overall Inquiry Expectations
■ [SCH V.08] express the result of any calculation
involving experimental data to the appropriate
number of decimal places or significant figures
■
Assessment
Checklist 5:
Learning Skills
(see
“Assessment
and Evaluation”
in the front
matter of
Teacher’s
Resource
CD-ROM)
Achievement
Chart Category
■
Communication
Learning Skills
■
Teamwork
Chemistry Bulletin
Student Textbook page 23
Answers to Making Connections Questions
1. The airplane should have received 21 163 L of fuel. This would have been calculated
as follows:
■ 7682 L (fuel already on board) × 0.803 kg/L (density of jet fuel) = 6169 kg
■ 22 300 kg (fuel needed in total) − 6169 kg (of fuel on board)
= 16 131 kg (fuel to be added)
■ 16 143 kg (of fuel to be added)/0.803 kg/L (density of fuel)
= 20 103 L (fuel to be added)
Note: The original edition of this book states, both in the feature and in question 1,
that the airplane should have received 21 163 L of fuel. Your copy of this book may
contain this quantity. In fact, the fuel quantity should be 20 089 L, which is the
answer students will get when they perform their calculations with a calculator.
2. The Mars Climate Orbiter (MCO) spacecraft was lost in September 1999 due to the
fact that one team of mission controllers was using metric units of measurement
while another team was using Imperial units during what officials described as a “key
spacecraft operation.” The two teams were apparently unaware that the units were
different, leading to a navigation error that put MCO more than 80 km closer to the
planet than intended during an orbit insertion maneuver on September 23. Project
officials believed that the spacecraft crashed to the surface after passing too deep into
the Martian atmosphere, and gave up looking for the spacecraft late September 24.
This is much like the “Gimli Glider” story in that the wrong type of unit of measurement was used to calculate key navigational information needed to safely place the
aircraft/spacecraft in the correct location. A similar incident could happen again since
several countries (including the United States) continue to use the Imperial system
instead of the metric system.
Section Review Answers
Student Textbook page 24
1. Accuracy is how close a measurement or calculation is to an expected or accepted
value while precision is the exactness of a measurement.
Chapter 1 Observing Matter • MHR
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UNIT 1 Chapter 1 OBSERVING MATTER
2. (a) kg
(c) mL
(e) m
(b) g
(d) cm or m
3. (a) 4
(c) 3
(b) 3
4. (a) 97.88
(c) 2.0 mL2
(b) 3.01 × 103 km2
(d) 0.12 g/mL
5. (a) Students may say a small graduated cylinder, or an appropriately calibrated
dropper. Those who have been exposed to a pipette should suggest it.
(b) Students may suggest a large beaker or graduated cylinder.
(c) graduated cylinder
(d) graduated cylinder or pipette
6. (a) The graph should show data points that are close to an expected value (high
accuracy) but fairly inexact (low precision)
high accuracy, low precision
5
Mass (g)
4
3
2
1
0
1
2
3
4
Trial Number
(b) The graph should show data points that are far from an expected value (low
accuracy) and highly inexact (low precision)
low accuracy, low precision
5
Mass (g)
4
3
2
1
0
1
2
3
4
Trial Number
1.3
Classifying Matter and Its Changes
Student Textbook pages 25–28
Physical and Chemical Changes in Matter, page 25
Classifying Matter, page 26
This section reviews physical and chemical changes, a topic that students investigated
in grade 9. The emphasis here will be on chemical changes, as this will lead into the
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MHR • Unit 1 Matter and Chemical Bonding
Answers to Analysis Questions
1. chemical and physical properties (students can be encouraged to be specific)
2. same answer as for question 1
Answers to Application Question
3. Encourage students to be supportive and respectful of one another’s work, especially
if you observe condescension or impatience.
Assessment and Evaluation
ThoughtLab/
ExpressLab/
Investigation
ThoughtLab:
Mixtures, Pure
Substances, and
Changes,
page 27
Curriculum
Expectation
■
Assessment
Tools/Technique
[SCH V.07] Communicate the procedures and
results of investigations for specific purposes by
displaying evidence and information, either in
writing or using a computer, in various forms,
including flow charts, tables, graphs, and
laboratory reports
■
Assessment
Checklist 5:
Learning Skills
(see
“Assessment
and Evaluation”
in the front
matter of
Teacher’s
Resource
CD-ROM)
Achievement
Chart Category
■
■
■
Knowledge/
Understanding
Inquiry
Communication
Learning Skills
■
■
Works
independently
Organization
Section Review Answers
Student Textbook page 28
1. Students should have no difficulty linking evaporation and melting with the addition
of energy, and condensation, freezing, and solidifying with the removal of energy.
removing energy
melting
solid
freezing (solidifying)
evaporation
liquid
condensation
gas
sublimation
adding energy
2. Sublimation should appear twice: once with the addition of energy (solid to gas) and
once with removal of energy (gas to solid).
Chapter 1 Observing Matter • MHR
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UNIT 1 Chapter 1 OBSERVING MATTER
sublimation
adding energy
solid
liquid
gas
sublimation
removing energy
3. Students should be able to assess their answers based on the definition of a mixture
(i.e., components retaining their own identity). Similarly, their classifications of heterogeneous and homogeneous mixtures should be based on whether the components
are visible or not.
4. Students should know that water is a pure substance (because electrolysis is required
to separate its component elements). How they know that other substances such as
carbon dioxide, and glucose, are pure substances may be more difficult for them to
explain. Chances are, they know because they have learned that these
substances are made up of elements and that they are not easily separated into their
component elements.
5. Students will likely suggest one or several series of filtering, as well as distillation.
Some students may suggest that a chemical could be added to clean the water (by
precipitation, for example), even if they do not know what chemical that might be.
Accept any reasonable answer.
6. This question provides a good “snapshot” of students’ prior knowledge and critical
thinking skills.
(a) Focus on students’ reasoning here, rather than the correctness of their answers.
Filtering and chemical purifying, for example, are reasonable ideas.
(b) The water likely will not be drinkable. However, some students may know of
chemical products available to campers for making water potable.
(c) Again, the emphasis here should be on reasoning.
Chapter 1 Review Answers
Student Textbook pages 29–31
Answers to Knowledge/Understanding Questions
1. (a) chemical
(c) physical
(b) physical
(d) chemical
2. Physical changes do not alter the composition of a substance, whereas chemical
changes do.
3. (a) dissolving; physical
(b) reactivity; chemical
(c) magnetism; physical
(d) freezing point; physical
(e) evaporation; physical
(f) decomposition or reactivity; chemical
4. Exp. I: low accuracy, fair precision; Exp. II: low accuracy, low precision; Exp. III: low
accuracy, high precision; Exp. IV: high accuracy, high precision
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MHR • Unit 1 Matter and Chemical Bonding
5. (a) Students’ answers will vary, but should not be more precise than to a single
decimal place for all three containers because none is finely calibrated. Typical
answers could be 125 mL (for A), 3.8 mL (for B), and 40 mL (for C)
(b) Assuming the previous values, approximately 170 mL.
(c) the graduated cylinder, because it is more finely calibrated
6. (a) 1.0 × 104 g
(b) 2.23 × 10−1 m
(c) 52 cm3
(d) 1.0 × 103 cm3
7. (a) 1
(b) 4
(c) 1
(d) 2
(e) 5
(f) 4
(g) 5
8. (a) If the value 5700 km were measured accurately, all four digits could be significant.
If rewritten in scientific notation as 5.7 × 103 , only two digits would be significant. The value could have three significant digits if you consider the fact that the
measured value could be 5769 or 5701.
(b) 5.7 × 103 km
(c) 5.700 × 103 km
9. (a) 8.73 mL
(b) 1.1 × 105 m2
2
(c) 2.2 × 10 kg/L
(d) 0.7
(e) 1.225 × 104 L
(f) 1.8 × 101 g/mL
10. (a) 6.21 × 103
(b) 3 × 101
2
(c) 6 × 10
(d) 1.73 × 101
11. 1.9 × 104 cm3
12. (a) 24˚C
(b) the tenths digit, to the right of the decimal
13. (a) chemical
(b) physical
(c) chemical
(d) physical
Answers to Inquiry Questions
14. (b) Student A
(c) Student D
(d) Student D
15. Pure hydrogen peroxide is a colourless, syrup-like liquid. Exposure to heat, light, and
chemical contaminants cause it to decompose, forming oxygen and water and releasing heat. In concentrated form, this heat may cause a violent explosion. This property
makes hydrogen peroxide (as a 90% solution) useful as a source of propulsion in
rocket fuel. Pharmacy-available hydrogen peroxide is typically a 3% solution, which is
adequate for safe handling. Nevertheless, any students wishing to experiment with
hydrogen peroxide should observe proper safety precautions. All used solutions
should be returned to you for safe disposal.
Students must recognize that they will be investigating the properties of a solution
of hydrogen peroxide and water. Knowing the physical and chemical properties of
water gives students a control against which they can compare their findings. For
example, students could investigate and compare pharmaceutical hydrogen peroxide
with water in terms of boiling point and freezing point. They can contrast its appearance, viscosity, “feel”, and (properly) smell with that of water. Chemically, students
could examine questions like: Does hydrogen peroxide react if it is left in sunlight? (It
should bubble.) or Added to a piece of potato? (It does—oxygen bubbles form slowly
on the potato, just as what happens with an open wound, due to the presence of an
enzyme called catalase.)
Chapter 1 Observing Matter • MHR
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UNIT 1 Chapter 1 OBSERVING MATTER
Students can perform the procedures they design to test their hypotheses if time
permits.
Answers to Communication Questions
16. Students can use print or electronic resources to “flesh out” their concept webs,
especially for uses of these chemicals.
17. Students likely will design a flowchart similar to the one shown on page 27 of the
student textbook plus identifying aluminum as an element, water as a compound,
cereal as a heterogeneous mixture, and apple juice as a homogeneous mixture.
18. Salad dressing is heterogeneous because the oil and water separate (unless the dressing
includes an emulsifying ingredient that keeps the two mixed).
Answers to Making Connections Questions
19. This question is a variation of the Unit 1 Project that appears on page 152 of the stu-
dent textbook, and may be easily used as an alternative unit assessment task.
Although this assignment does not require students to come in direct contact with
any chemical products per se, nevertheless, be sure to caution students about safe handling and proper respect for any chemical products in the home, no matter how
benign they appear to be.
20. Students might suggest questions such as: What is the chemical composition of the
chemical? Does it have a common name by which people know it better? What, precisely, does it do (i.e., what are its physical and chemical properties)? Where can I go
to learn more about this chemical and the issue that is supposedly associated with it?
(Students questions should indicate some degree of skepticism, as well as a desire to
find out more so that more informed judgments and assessments can be made.)
21. (a) Students will likely identify environmental connections as the most important.
(b) The class may easily split here. Some students may identify societal connections as
most important. Others may choose technology. The selection is much less
important than the reasons students provide for it.
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MHR • Unit 1 Matter and Chemical Bonding