Name
Date
Describing Matter
What Properties Describe Matter?
1a. CLASSIFY The melting point of table salt is 801°C. Is this a
physical or chemical property?
b. DRAW CONCLUSIONS Helium does not usually react with other
substances. Does this mean that helium has no chemical
properties? Explain.
I get it! Now I know that matter is described by its
I need extra help with
7B
Class
Name
Date
Class
Describing Matter
On a separate sheet of paper, explain what matter is and how the physical and chemical
properties of matter are alike and different.
7C
Name
Date
Class
Describing Matter
Understanding Main Ideas
Classify each of the following properties by writing physical or chemical on the line at
the left.
1.
Texture
2.
Ability to react with other substances
3.
Ability to conduct heat
4.
Hardness
5.
Lack of ability to rust
6.
State
Building Vocabulary
If the statement is true, write true. If the statement is false, change the underlined word
or words to make the statement true.
Table salt is an example of a(n) substance.
7.
The study of matter and how it changes is
8.
called physics.
Matter is anything that has color and takes up
9.
space.
10.
A(n) physical property of a substance can only
be observed if the substance changes into a different substance.
The boiling point of a substance is a(n)
11.
chemical property.
7D
Name
Date
Class
Describing Matter
Read the passage and study the diagram below it. Then use a separate sheet of paper to
answer the questions that follow.
Degradable Plastics
A chemical property is a characteristic of a substance that describes its ability to change into different
substances. One way in which substances are changed is to be broken down into simpler substances.
Materials that are degradable can be broken down easily in the environment. Most plastics are not
degradable, remaining in the environment for a long time. But Today there are two main types of plastics
that are degradable: photodegradable (photo- means “light”) and biodegradable (bio- means “life”).
Photodegradable plastics break down into smaller pieces after exposure to a certain amount of sunlight.
Biodegradable plastics contain natural substances in addition to the plastic. The most common additive is
cornstarch. Cornstarch is made up of sugar that is broken down by microorganisms. When this happens,
the plastic breaks down into smaller pieces.
One area in which degradable plastics are being used today involves erosion control. In places where
land has been cleared, such as during highway construction, erosion control blankets made with layers
of degradable plastic and straw can be placed on the soil. The blanket keeps the soil from being washed
away until new plants have a chance to grow. Once the blanket has broken down, the plants’ roots will
be able to keep the soil in place.
1. Do you think photodegradable plastic that is buried in a landfill will
break down quickly? Explain.
2. Most landfills contain very little air and moisture, which many
microorganisms need to survive. How do you think these conditions
affect biodegradable plastic buried in a landfill?
3. Why do you think it is important that an erosion control blanket
break down after a few weeks or months?
7E
Name
Date
Class
Describing Matter
Write the letter of the correct answer on the line at the left.
1.
The physical property that makes metal
pots good for cooking is
A flexibility
B electrical conductivity
C flammability
D heat conductivity
2.
Which of the following is true
about matter?
A It is a solid that takes up space.
B It has mass and takes up space.
C It has mass and is usually a liquid.
D It is always a substance.
3.
Which of the following is not true about
a pool of water and a piece of ice?
A They have the same composition.
B They are in different states of matter.
C They have different chemical properties.
D They have different physical properties.
4.
Characteristics used to describe
matter are called
A physical properties
B chemical properties
C both A and B
D neither A nor B
Fill in the blank to complete each statement.
5. Solid, liquid, and gas are the three
of matter.
6. The metal tungsten is used in incandescent light bulbs because of its
property of
.
7.
is the study of matter and the changes in matter.
8. The ability of iron to rust is a(n)
9. A(n)
property.
is a single kind of matter that has a specific composition.
10. Another term for the ability to burn is
.
7F
Name
Date
Classifying Matter
What Is Matter Made Of?
1a. REVIEW What holds the hydrogen and oxygen atoms together in a
water molecule?
b. IDENTIFY Table sugar has the chemical formula C12H22O11. What
is the ratio of carbon atoms to oxygen atoms in this compound?
c. DRAW CONCLUSIONS Two formulas for compounds containing
hydrogen and oxygen are H2O and H2O2. Do these formulas
represent the same compound? Explain.
I get it! Now I know that all matter is made up of
I need extra help with
What Are Two Types of Mixtures?
I get it! Now I know that the two types of mixtures are
I need extra help with
13B
Class
Name
Date
Class
Classifying Matter
On a separate sheet of paper, explain how the following terms are related: element,
atom, molecule, chemical bond, compound, mixture, and substance.
13C
Name
Date
Class
Classifying Matter
Understanding Main Ideas
Answer the following questions on a separate piece of paper.
1. Describe the basic particle from which all elements are made.
2. How are elements and compounds related?
3. What is the difference between a chemical symbol and a
chemical formula?
4. What are two ways in which mixtures differ from compounds?
5. List four methods that can be used to separate mixtures.
Building Vocabulary
Match each term with its definition by writing the letter of the correct definition in the
right column on the line beside the term in the left column.
6.
atom
a. shows the elements and ratio of atoms in a
compound
7.
chemical bond
b. a group of two or more atoms held together by
chemical bonds
8.
molecule
c. a substance made of two or more elements
chemically combined in a set ratio
9.
element
d. a substance that cannot be broken down into any
other substance
10.
chemical formula
e. two or more substances together in the same place
but not chemically combined
11.
compound
12.
mixture
f. the basic particle of any element
g. the force of attraction between two atoms
13D
Name
Date
Class
Classifying Matter
Collect the items in the materials list and perform the steps in the procedure. Then
answer the questions that follow on a separate piece of paper.
Separating a Mixture
Materials
mixture made of sand, sugar, and wood chips
plastic dishpan
strainer
slotted spoon
coffee filters
measuring cup
tap water
colander
wooden spoons
Procedure
1. Place several cups of the sand, sugar, and wood chip mixture in the
plastic dishpan.
2. Carefully add enough water to the dishpan to cover the mixture.
3. Devise a plan to separate the three ingredients in the mixture, using
only the materials listed above.
4. After obtaining your teacher’s approval, try out your plan.
Analyze and Conclude
1. How were you able to separate the wood chips from the mixture?
2. How were you able to separate the sand from the mixture?
3. How could you separate the sugar from the mixture?
4. Did any of the ingredients form a solution with the water? How can
you tell?
13E
Name
Date
Class
Classifying Matter
Write the letter of the correct answer on the line at the left.
2.
A
B
C
D
A molecule is the smallest part of
an element
a compound
a substance
an atom
A mixture of iron and sulfur can be
separated by
A magnetic attraction
B distillation
C evaporation
D filtration
4.
A
B
C
D
Compounds are formed as a result of
physical combination
chemical combination
distillation
filtration
The ratio of hydrogen atoms to sulfur
atoms in sulfuric acid, H2SO4 is
A 2 to 4
B 1 to 2
C 2 to 1
D 1 to 4
1.
3.
If the statement is true, write true. If the statement is false, change the underlined word
or words to make the statement true.
5.
Salad dressing is an example of a homogeneous mixture.
6.
The simplest type of substance is a(n) compound.
When elements combine to form compounds, their properties
7.
do not change.
8.
The chemical symbol for water is H2O.
9.
Substances in a mixture keep their own properties.
10.
The substances in a heterogeneous mixture can usually be seen
and are easily separated.
13F
Name
Date
Measuring Matter
What Units Are Used to Express Mass and Volume?
1a. EXPLAIN Why is mass more useful than weight for measuring
matter?
I get it! Now I know that the SI unit for mass is
and the SI unit for volume is
I need extra help with
How Is Density Determined?
2a. IDENTIFY Maple syrup will (float/sink) in water because its density is
greater than 1 g/cm3.
b. CALCULATE What is the mass of a sample of a substance with a volume
of 120 mL and a density of 0.75 g/mL?
c.
CHALLENGE
Liquid water and ice are the same substance,
H2O. How would you explain why ice floats in water?
I get it! Now I know density is calculated by
I need extra help with
19B
Class
Name
Date
Class
Measuring Matter
On a separate sheet of paper, describe what mass and volume are, in what units they are
measured, how they determine density, and why density is important.
19C
Name
Date
Class
Measuring Matter
Understanding Main Ideas
Use the figure to answer the following questions on a separate sheet of paper.
1. What is the volume of the solid in the figure? Show your work.
Be sure to use correct units of measurement.
2. The solid has a mass of 180 g. What is the density of the solid? Show
your work. Be sure to use correct units of measurement.
3. Would the solid have a mass of 180 g on the moon? Would it have
the same weight on Earth as on the moon? Explain your answers.
4. The solid sinks to the bottom when placed in a container of water.
What does this tell you about its density?
5. Will every solid with the same dimensions have the same density?
Explain your answer.
Building Vocabulary
Write a definition for each of these terms on a separate piece of paper.
6.
7.
8.
9.
10.
International System of Units
mass
volume
density
weight
19D
Name
Date
Class
Measuring Matter
Read the passage and study the figure below it. Then use a separate sheet of paper to
answer the questions that follow.
Units of Measurement and Shared Knowledge
Communication among scientists is easier when they all use the same standard units of measurement.
Imagine trying to communicate information to a civilization on another planet. You do not speak the
same language. You may not even share the same knowledge. In 1972, scientists working on the Pioneer
10 spacecraft faced these problems. Because this was the first spacecraft to leave the solar system,
scientists attached a small plaque to it, similar to one in the figure below. In case it should ever be found
by an extraterrestrial civilization, scientists wanted to communicate some information about where the
spacecraft came from.
Unfortunately, an extraterrestrial would probably not understand units such as meters or seconds. What
kind of measurements would members of an extraterrestrial civilization understand? Eventually, scientists
decided to use a type of energy given off by particles of hydrogen as the basis for a unit of length. A
representation of hydrogen particles is labeled A on the plaque. The starburst pattern (labeled B) will
help extraterrestrial scientists locate our solar system in the galaxy. The longest horizontal line represents
the distance from our sun to the center of the galaxy. The shorter solid lines represent directions and
distances from our sun to other stars.
1. Why didn’t scientists use units of measurement on the Pioneer
plaque that societies on Earth are familiar with?
2. Do you think it would be easier to communicate information
about weight or mass to an extraterrestrial civilization? Explain.
(Hint: Consider which of these two measurements is constant.)
3. At the bottom of the Pioneer plaque there is a diagram of our
solar system (labeled C). What do you think the small drawing of
the Pioneer spacecraft and the arrow coming from the third planet
represent?
19E
Name
Date
Class
Measuring Matter
Write the letter of the correct answer on the line at the left.
1.
A balloon filled with air does not rise
as high as a balloon filled with helium.
What does this tell you about the density
of helium?
A Helium is more dense than air.
B Helium is less dense than air.
C The two gases have the same density.
D When heated, helium becomes more dense.
2.
The amount of matter in an object
is a measure of its
A volume
B density
C weight
D mass
3.
The formula for calculating density is
A Mass × Volume
B Mass × Weight
4.
Which of the following statements
about the mass of an object is correct?
A Mass changes with location.
B Mass remains constant.
C Mass changes with altitude.
D Mass changes with gravity.
C
D
Mass
Volume
Volume
Mass
If the statement is true, write true. If the statement is false, change the underlined word
or words to make the statement true.
5.
The SI unit of mass is the cubic meter.
6.
One liter is equal to 100 milliliters.
7.
An object’s weight is less on the moon than on Earth. On the
moon, the object’s mass decreases.
8.
An object that floats in water has a density less than 1 g/mL.
Four measurable properties of matter are mass, weight,
9.
volume, and pressure.
10.
The SI unit of volume is the kilogram.
19F
Name
Date
Class
Changes in Matter
What Happens to a Substance in a Physical Change?
1a. CLASSIFY Mark all the processes that are physical changes.
drying wet clothes
cutting snowflakes out of paper
lighting a match from a matchbook
melting butter for popcorn
b. APPLY CONCEPTS Describe three physical changes that occur in nature.
I get it! Now I know that a substance that undergoes a physical change is
I need extra help with
What Happens to a Substance in a Chemical Change?
2a. NAME A chemical reaction is another name for a chemical
(combustion/change).
b. PREDICT What kind of chemical change do you think occurs
when a banana peel turns brown in the open air? Explain.
c.
CHALLENGE
Assuming no mass escapes, explain why the mass
of a rusted nail is greater than the mass of a nail before it rusted.
I get it! Now I know that when a substance undergoes a chemical change,
I need extra help with
29B
Name
Date
Changes in Matter
How Are Changes in Energy and Matter Related?
3a. IDENTIFY What energy transformation takes place when you exercise?
b. ANSWER
How is matter described?
I get it! Now I know that every chemical and physical change includes
I need extra help with
29C
Class
Name
Date
Class
Changes in Matter
On a separate sheet of paper, explain how physical and chemical changes are alike and
different. Be sure to discuss the role of energy in the changes.
29D
Name
Date
Class
Changes in Matter
Understanding Main Ideas
Identify the type of change or changes that apply to each description by writing P for
physical change, C for chemical change, and PC for both on the appropriate line.
1.
Occurs when energy is added or removed.
2.
A new substance is produced.
3.
A substance changes form, but it remains the same substance.
4.
Freezing water is an example.
5.
Rusting metal is an example.
Building Vocabulary
Match each term with its definition by writing the letter of the correct definition in the
right column on the line beside the term in the left column.
6.
temperature
a. the energy stored in the chemical bonds between
atoms
7.
exothermic change
b. a change in which energy is absorbed
8.
chemical energy
c. a measure of the energy of motion of the particles of
matter
9.
endothermic change
d. the total energy of all of the particles in an object
thermal energy
e. the fact that matter is neither created nor destroyed
in any physical or chemical change
10.
11.
law of conservation of
mass
12.
physical change
13.
chemical change
f. a change in which energy is released
g. a change in matter that produces one or more new
substances
h. alters the form or appearance of matter but does
not turn any substance in the matter into another
substance
29E
Name
Date
Class
Changes in Matter
Collect the items in the materials list and perform the steps in the procedure. Then
answer the questions that follow on a separate piece of paper.
Is It Chemical or Physical?
Materials
40 mL skim milk
3 plastic cups
plastic spoon
2 pieces of paper
10 mL vinegar
coffee filter
baking soda
Procedure
1. Pour the skim milk into a plastic cup. Add the vinegar and stir to mix.
2. Pour the mixture through a coffee filter into another cup.
3. Use a plastic spoon to scrape off the material that collects on the
filter. Be careful not to tear the filter. Place this material in a third
cup. If this material is too thick, add a small amount of water and stir.
4. Add a pea-sized amount of baking soda to the material in the third
cup. Stir to mix.
5. You have made a natural glue. Try gluing two pieces of paper
together to see how well it works.
Analyze and Conclude
1. Describe the properties of the ingredients that you used to make
the glue.
2. Describe the properties of the glue that you made.
3. Is making glue an example of a chemical change or a physical
change? Explain how you know.
4. Did a change in energy occur with this change in matter? Explain.
29F
Name
Date
Class
Changes in Matter
Write the letter of the correct answer on the line at the left.
1.
Which of the following is not a physical
change?
A glass breaking
B iron rusting
C ice melting
D sugar dissolving
2.
Which of the following is not a
chemical change?
A leaves turning color
B fruit ripening
C silver tarnishing
D food coloring dissolving in water
3.
Butter is melted in a pan. Which of the
following is true about the change?
A It is a physical change that releases energy.
B It is a chemical change that absorbs energy.
C It is a physical change that absorbs energy.
D It is a chemical change for which there is no
change in energy.
4.
The energy stored in the bonds
between atoms is
A chemical energy
B thermal energy
C electrical energy
D endothermic energy
Fill in the blank to complete each statement.
5. A(n)
change releases energy.
6. New substances are produced by a(n)
7.
change.
is related to the energy of motion of the particles of matter.
8. The law of
of mass states that in any physical or chemical
change, matter is neither created nor destroyed.
9.
energy naturally flows from warmer matter to cooler matter.
10. The form or appearance of matter is altered during a(n)
change.
29G
Name
Date
Class
States of Matter
How Do You Describe a Solid?
1a. IDENTIFY The two types of solids are
and
.
b. EXPLAIN Are the particles in a solid motionless? Explain your answer.
c. DRAW CONCLUSIONS Candle wax gradually loses its shape
as it is heated. What type of solid is candle wax? Explain.
I get it! Now I know that a solid has a definite shape and volume because
I need extra help with
How Do You Describe a Liquid?
2a. NAME A substance that flows is called a
.
b. DESCRIBE Why is a liquid able to flow?
c. COMPARE AND CONTRAST How do liquids with a high
viscosity differ from liquids with a low viscosity?
I get it! Now I know that a liquid has a definite volume but not a definite shape
because
I need extra help with
47B
Name
Date
States of Matter
How Do You Describe a Gas?
3a. DESCRIBE Describe how the motions of gas particles
are related to the pressure exerted by the gas.
b. RELATE CAUSE AND EFFECT Why does pumping more air
into a basketball increase the pressure inside the ball?
I get it! Now I know that a gas has neither a definite shape nor volume
because
I need extra help with
47C
Class
Name
Date
Class
States of Matter
On a separate sheet of paper, draw a representation of the molecules in a solid, a liquid,
and a gas.
47D
Name
Date
Class
States of Matter
Understanding Main Ideas
Answer the following questions in the space provided.
1. What are the general characteristics of a solid?
2. How do crystalline solids differ from amorphous solids?
3. How are liquids described in terms of shape and volume?
4. Explain why a sewing needle can float on the surface of water in
a glass.
5. What determines the shape and volume of a gas inside a container?
Building Vocabulary
If the statement is true, write true. If the statement is false, change the underlined word
or words to make the statement true.
6.
Rubber and glass, which become softer as they are heated, are
examples of crystalline solids.
When you see steam, fog, or clouds, you are seeing water in
7.
the liquid state.
8.
9.
10.
The volume of a gas is the force of its outward push divided by
the area of the walls of the container.
A(n) gas has a definite volume but no definite shape.
A(n) fluid has a definite shape and volume.
47E
Name
Date
Class
States of Matter
Read the passage and study the diagram below it. Then use a separate sheet of paper to
answer the questions that follow the diagram.
Bottle-Making
You learned in this section that glass is an amorphous solid. This property allows it to be molded into
shaped such as bottles. Bottles are usually made with an individual section (IS) machine, which is actually
a series of automated machines that carry out each step of the bottle-making process. First, very hot,
softened glass exits a furnace. Next, the softened glass is cut into lumps, or sections. Each lump of glass
moves through the machine to a mold. Air is blown into the mold with great force. This forms the glass
inside the mold into a hollow shape called a parison (PAYR uh suhn). Next, the parison is placed in a
second mold called the finishing mold. Air is forced into the finishing mold to bring the bottle to its final
shape. The entire molding process takes about 11 seconds.
At this point, the bottle is still very hot. After leaving the finishing mold, it travels down a conveyor belt
on which it cools and hardens. At the same time, a chemical is usually sprayed on the bottle to give it a
hard coating that is resistant to scratches.
1. Why do you think bottles are made from amorphous solids such as
plastic and glass? Why aren’t they made from crystalline solids?
2. What must the melting point of the mold be compared to the
temperature at which glass gets soft? Why?
3. When the parison is placed on the second mold, it doesn’t yet have
the exact shape of a finished bottle. Is the parison’s viscosity low or
high? Explain.
4. Glass is sometimes called a supercooled liquid. Why do you think
this is so?
47F
Name
Date
Class
States of Matter
Fill in the blank to complete each statement.
1. The amount of space that matter fills is its
.
2. A state of matter with a definite volume, but no definite shape is
a(n)
.
3. A(n)
will always take the shape and volume of its container.
4. The
substance.
is a measure of the average speed of the particles in a
5. A(n)
has a definite volume but no shape of its own.
6. The
of a gas is the force of its outward push divided by the
area of the walls of its container.
If the statement is true, write true. If the statement is false, change the underlined word
or words to make the statement true.
7.
Viscosity is the inward force among the molecules of a liquid.
8.
A(n) amorphous solid has a definite melting point.
9.
Both gases and liquids are fluids.
10.
All solids have a closely packed, fixed arrangement of particles.
47G
Name
Date
Class
Changes of State
What Happens to the Particles of a Solid as It Melts?
1a. IDENTIFY The change in state from a solid to a liquid is called
.
b. COMPARE AND CONTRAST How does what happens to the particles in a
substance during melting differ from what happens during freezing?
I get it! Now I know that melting occurs when the particles in a solid
I need extra help with
What Happens to the Particles of a Liquid as It Vaporizes?
2a. IDENTIFY The change in state from a liquid to a gas is called
b. APPLY CONCEPTS How does the thermal energy of water vapor change
as the vapor condenses?
c. RELATE CAUSE AND EFFECT Why do clouds form before it rains?
I get it! Now I know vaporization occurs when the particles in a liquid
I need extra help with
55B
.
Name
Date
Class
Changes of State
What Happens to the Particles of a Solid as it Sublimes?
3a. IDENTIFY What is dry ice?
b. PREDICT If you allowed dry ice to stand in a bowl at room
temperature for several hours, what would be left?
c. ANSWER
Why does a substance change states?
I get it! Now I know that sublimation occurs when the particles in a solid
I need extra help with
55C
Name
Date
Class
Changes of State
One winter morning, you wake up to see the outside thermometer below 0°F. You find
ice frozen along the sill of the inside of your window. The windowsill was dry when you
went to bed. Describe how you think the ice formed overnight.
55D
Name
Date
Class
Changes of State
Understanding Main Ideas
Fill in the blank to complete each statement.
1. Both sublimation and
substance.
2. The
occur only on the surface of the
of melting is freezing.
3. When butter is heated it melts, and when that melted butter cools and solidifies the
process is called
.
4. When a gas turns to a liquid, the energy of the particles
5. Vaporization is the reverse of
.
.
Building Vocabulary
Match each term with its definition by writing the letter of the correct definition in the
right column on the line beside the term in the left column.
6.
melting
a. the change from a liquid to a gas
7.
freezing
b. the change from a solid to a liquid
8.
condensing
c. the change from a solid to a gas
9.
vaporizing
d. the change from a gas to a liquid
subliming
e. the change from a liquid to a solid
10.
55E
Name
Date
Class
Changes of State
Read the passage and study the diagram below it. Then use a separate sheet of paper to
answer the questions that follow the diagram.
Freeze-Drying
Freeze-drying is a method of preserving food. In the first step of this process, the food is frozen, which
converts the water in the food to ice. Next, the frozen food is placed into a special chamber. Most of the
air in this chamber is pumped out, causing the pressure inside to decrease. At low pressure, sublimation
occurs. About 98 percent of the water content of food can be removed with this method.
Freeze-dried foods are commonly eaten by campers and soldiers. One advantage of these foods is that
they do not have to be refrigerated. Refrigeration slows the decay of foods by organisms such as bacteria
and fungi. Because these organisms cannot reproduce without water, however, freeze-dried foods can
be stored at room temperature. Freeze-dried foods are also lightweight. Removing the water from food
reduces its mass by about 90 percent. In addition, freeze-dried foods are easy to prepare; they can be
restored to their original composition just by adding water.
Food is not the only thing that can be freeze-dried. Florists sometimes freeze-dry flower arrangements
to preserve them for up to three years. Scientists freeze-dry cells, tissues, and other samples so that they
can be used in research. In addition, books and other papers that have become wet due to flooding can
sometimes be saved by freeze-drying.
1. What two changes of state are involved in freeze-drying?
2. Suppose you have 100 kg of fresh strawberries. What would be the
approximate mass of the strawberries after freeze-drying?
3. Why do you think campers and soldiers use freeze-dried food?
4. What is one advantage that freeze-dried foods have over frozen
foods?
5. Is freeze-drying a physical change or a chemical change? Explain.
55F
Name
Date
Class
Lesson Quiz
Write the letter of the correct answer on the line at the left.
1.
Which of the following describes the
process of freezing?
A Freezing occurs when the temperature of a
substance drops to 0°C.
B Freezing occurs when the particles of a
solid vibrate so fast that they break free.
C Freezing occurs when the temperature
drops enough a gas turns into a solid.
D Freezing occurs when the particles in a
liquid slow down and take fixed positions.
2.
The process that makes ice cubes
shrink as they sit in a freezer is called
A sublimation
B condensation
C freezing
D boiling
3.
The temperature at which a liquid
turns to a gas is
A called the freezing point
B called the boiling point
C 100°C
D the same for an amorphous or a crystalline
solid
4.
Particles of which of the following
have the greatest thermal energy?
A a liquid
B a crystalline solid
C a gas
D an amorphous solid
If the statement is true, write true. If the statement is false, change the underlined
word or words to make the statement true.
Sublimation and boiling both happen at the surface of
5.
the substance.
Vaporization is the reverse of condensation.
6.
The temperature at which a liquid turns to a gas is called
7.
the boiling point.
8.
Boiling is the reverse of freezing.
9.
Water particles in gas coming off of a pan of boiling water
are moving slower than the particles of the water in the pan.
10.
Evaporation and condensation are both types of vaporization.
55G
Name
Date
Class
Gas Behavior
How Are Pressure and Temperature of a Gas Related?
I get it! Now I know that when the temperature of a gas at a constant volume
increases,
I need extra help with
How Are Volume and Temperature of a Gas Related?
1a. IDENTIFY The graph of Charles’s law shows that the volume of a gas is to its Kelvin temperature at constant pressure.
b. PREDICT Suppose the gas in Figure 4 could be cooled to 100 K
(−173°C). Predict the volume of the gas at this temperature.
I get it! Now I know that when the temperature of a gas is decreased
at constant pressure,
I need extra help with
61B
Name
Date
Class
Gas Behavior
How Are Pressure and Volume of a Gas Related?
2a. IDENTIFY The graph of Boyle’s law shows that the gas pressure is to volume at constant temperature.
b. READ GRAPHS Use the graph that you made in the Analyzing Data
feature to find the pressure of the gas when its volume is 125 mL.
I get it! Now I know that when the pressure of a gas at a constant temperature is
increased,
I need extra help with
61C
Name
Date
Class
Gas Behavior
You take a sealed, air-filled balloon, squeeze it and then release it. Next you take the
balloon and place it in a refrigerator for half an hour, then remove it. In each case, explain
the changes in volume, pressure, and temperature.
61D
Name
Date
Class
Gas Behavior
Understanding Main Ideas
If the statement is true, write true. If the statement is false, change the underlined word
or words to make the statement true.
1.
If the temperature of a gas is constant, when the pressure is
increased, the volume decreases.
2.
If the air pressure inside an inner tube is constant, when the
temperature of the air is increased, the volume decreases.
3.
The graph of the relationship between the volume of a gas at
constant temperature and its pressure is a(n) line.
4.
If the temperature of a gas inside a sealed, rigid container is
decreased, its pressure decreases.
5.
The graph for Charles’s law shows that the volume of a gas at
constant pressure is inversely proportional to its temperature.
6.
If a gas at constant pressure inside a cylinder topped by a
movable piston is heated, the volume of the gas will increase and push the piston
outward.
Building Vocabulary
Fill in the blank to complete each statement.
7. When the graph relating two variables is a straight line passing though the origin,
the variables are
proportional.
8. According to
law, when the pressure of a gas at constant
temperature is increased, the volume of the gas decreases.
9. According to
law, when the temperature of a gas is increased
at constant pressure, its volume increases.
10. When the product of two variables is constant, the variables are
proportional to each other.
61E
Name
Date
Class
Gas Behavior
Read the passage and study the graphs below it. Then use a separate sheet of paper to
answer the questions that follow the graphs.
Grasping Gas Graphs
You have examined the relationship between the temperature and volume of a gas, and between the
pressure and volume of a gas. Suppose a scientist wants to determine whether the number of particles
of a gas is related to its pressure. Data for this experiment can be collected by increasing the number of
gas particles in a container with a constant volume and temperature, and measuring the pressure of the
gas. The number of gas particles can be increased by pumping more gas into the container. Sample data
from such an experiment are shown by the solid line in Figure 1. The dotted line shows how the resulting
graph can be extended.
The relationship between the number of particles of a gas and its volume at a constant temperature can
be determined in a similar way. Data for this experiment can be collected by increasing the number of
gas particles in a cylinder that has a movable piston and measuring the effect on the volume. The graph
in Figure 2 shows sample data from such an experiment.
1. What is the manipulated variable in each graph? What is the
responding variable?
2. What is the relationship between the number of gas particles and
pressure? Are these two variables directly proportional or do they
vary inversely?
3. What is the relationship between the number of gas particles and
volume? Are these two variables directly proportional or do they vary
inversely?
4. When the number of gas particles in a container with constant
volume decreases, how will the pressure of the gas change?
5. When the number of gas particles at constant pressure increases,
how will the volume of the gas change?
61F
Name
Date
Class
Gas Behavior
Write the letter of the correct answer on the line at the left.
1.
At constant temperature, when
the volume of a gas is decreased, what
happens to its pressure?
A It decreases.
B It will vary.
C It increases.
D It remains constant.
2.
At constant pressure, when the
temperature of a gas is decreased, what
happens to its volume?
A It decreases.
B It will vary.
C It increases.
D It remains constant.
3.
At constant pressure, how are the
temperature and volume of a gas related?
A They are inversely proportional.
B They are directly proportional.
C They are constant.
D They are indirectly proportional.
4.
If the sun shining through windows
heats the air in a sealed room, what
happens to the air pressure in that room?
A It decreases.
B It will vary.
C It increases.
D It remains constant.
Fill in the blank to complete each statement.
5. When Martin pushes down on the handle of his bicycle pump, the air pressure within
the pump
.
6.
law describes the relationship between a gas’s volume and
pressure when its temperature is constant.
7.
law describes the relationship between a gas’s temperature and
volume when its pressure is constant.
8. At constant temperature, the pressure and volume of a gas are
proportional.
9. At constant volume, when the temperature of a gas decreases, the
pressure
.
10. When the graph relating two variables is a straight line passing through the origin,
the variables are
proportional to each other.
61G
Name
Date
Class
Introduction to Atoms
How Did Atomic Theory Develop?
1a. DEFINE An atom is
b. DESCRIBE Bohr’s model of the atom consisted of a central surrounded by electrons moving in specific
.
c. COMPARE AND CONTRAST How is the cloud model of the atom different
from Bohr’s model? I get it! Now I know that atomic theory changed with time because
I need extra help with
How Is the Modern Model of the Atom Described?
2a. EXPLAIN What is atomic number? How is atomic number used to
distinguish one element from another?
b. APPLY CONCEPTS The atomic number of nitrogen is 7. How many
protons, neutrons, and electrons make up an atom of nitrogen-15?
I get it! Now I know that the modern model of the atom can be described as
I need extra help with
79B
Name
Date
Class
Introduction to Atoms
On a separate sheet of paper, describe the modern model of the atom.
79C
Name
Date
Class
Introduction to Atoms
Understanding Main Ideas
Answer the following questions on a separate sheet of paper.
1.
2.
3.
4.
5.
6.
What three particles are found in an atom?
Which two particles are found in an atom’s nucleus?
Explain why scientists use models to study atoms.
Which two particles in an atom are equal in number?
How are elements identified in terms of their atoms?
What two particles account for almost all of the mass of an atom?
Building Vocabulary
Fill in the blank to complete each statement.
7. The
is the very small, dense center of an atom.
8. The positively charged particle of an atom is called a(n)
9. A particle with no charge is a(n)
.
.
10. A(n)
is the particle of an atom that moves rapidly in the
cloudlike region around the nucleus.
11. The
nucleus of every atom of an element.
tells the number of protons in the
12. Atoms of the same element that have the same number of protons but different
numbers of neutrons are called
.
13. The sum of protons and neutrons in the nucleus of an atom is the
.
14. Scientists will often use a(n)
about the natural world.
, an object that helps explain ideas
79D
Name
Date
Class
Introduction to Atoms
Read the passage and study the figure below it. Then use a separate sheet of paper to
answer the questions that follow the figure.
Exactly How Small Is It?
Measuring the size of an atom is not easy. For one thing, an atom is very, very tiny. Scientists, however,
have developed several ways to estimate the relative sizes of atoms. For elements that exist as two
identical molecules bonded together, such as oxygen and hydrogen, scientists can use a technique called
X-ray diffraction to estimate the distance between the nuclei. Once scientists do that, they can calculate
the atomic radius, which is one-half the distance between the nuclei.
It’s important to remember that the atomic radius is not a measurement of a single atom’s size but
only its size relative to other atoms. In other words, scientists know that oxygen atoms are larger than
hydrogen atoms, but they don’t know the exact size of any single atom of oxygen. When comparing
sizes of atoms, one must be careful to compare sizes based on similar measuring techniques.
The figure below shows the atomic radii of several elements. The atomic radius is given in units of
picometers (pm). One picometer is equal to 0.000000000001 meter.
1.
2.
3.
4.
What part of an atom determines its size?
Why is it difficult to measure the size of an atom?
What is the distance between nuclei in a hydrogen molecule (H2)?
What would be the distance between nuclei of a bromine
molecule (Br2)?
5. What is the atomic radius of oxygen in meters?
6. Which atoms are relatively larger than oxygen atoms?
79E
Name
Date
Class
Introduction to Atoms
Write the letter of the correct answer on the line at the left.
1.
The positively charged particle in an
atom’s nucleus is the
A electron
B neutron
C proton
D isotope
2.
An element’s identity can be
determined from its
A atomic number
B number of neutrons
C number of isotopes
D energy levels
3.
The smallest particle an element can
be divided into is the
A electron
B neutron
C isotope
D atom
4.
The model of the atom that described
electrons scattered throughout a ball of
positive charge was proposed by
A Niels Bohr
B Ernest Rutherford
C J. J. Thomson
D John Dalton
If the statement is true, write true. If the statement is false, change the underlined word
or words to make the statement true.
An element’s mass number tells the number of protons in its
5.
nucleus.
Negatively charged particles in an atom are called electrons.
6.
7.
The cloud model of the atom describes the location of
electrons as specific orbits around the nucleus.
8.
Atoms with the same number of protons but different numbers
of neutrons are called isomers.
The sum of the protons and neutrons in an atom is called the
9.
atomic number.
An object that helps explain ideas about the natural world is
10.
called a model.
79F
Name
Date
Class
Organizing the Elements
What Did Mendeleev Discover?
1a. REVIEW In what order did Mendeleev arrange the elements in his
periodic table?
b. PREDICT How could Mendeleev predict the properties of
elements that had not yet been discovered?
I get it! Now I know that when Mendeleev arranged the elements in
order of increasing atomic mass,
I need extra help with
What Information Does the Periodic Table Contain?
2a. COMPARE AND CONTRAST Describe two differences between
Mendeleev’s periodic table and the modern periodic table. b. INTERPRET TABLES An atom of which element has 47 protons in its
nucleus?
I get it! Now I know that information found on the periodic table for each element
includes
I need extra help with
87B
Name
Date
Class
Organizing the Elements
How Is the Periodic Table Useful?
3a. NAME The rows in the periodic table are called
The columns in the periodic table are called
b. DESCRIBE What do elements in the same group in the periodic table
have in common?
c. PREDICT Use the periodic table to name two elements that you would
expect to have properties very much like those of calcium (Ca).
I get it! Now I know that the periodic table is useful because
I need extra help with
87C
.
.
Name
Date
Class
Organizing the Elements
On a separate sheet of paper, compare and contrast Mendeleev’s periodic table with the
modern periodic table.
87D
Name
Date
Class
Organizing the Elements
Understanding Main Ideas
The diagram below is a square from the periodic table. Label the four facts shown about each
element.
1.
2.
3.
4.
Answer the following questions in the spaces provided.
5. In what order did Mendeleev arrange the elements in the periodic table?
6. What do elements in the same column in the periodic table have in
common?
7. What can you predict about an element from its position in the
periodic table?
Building Vocabulary
Fill in the blank to complete each statement.
8. An element’s is its row in the periodic table.
9. The
all isotopes of that element.
of an element is the average mass of
10. A(n)
is an abbreviation for the name of
an element and usually has either one or two letters.
87E
Name
Date
Class
Organizing the Elements
Read the passage and look at the diagram and table below it. Then use a separate sheet
of paper to answer the questions that follow the diagram and table.
Properties of a “Missing” Element
To some scientists of the early 1870s, Dmitri Mendeleev’s periodic table of the elements was not very
good. They criticized the table because it had gaps in it. Mendeleev, however, believed the gaps would
someday be filled by elements that had not yet been discovered. In 1871, he predicted some of the
properties of a yet-to-be-discovered element. He called it “ekasilicon.” The “missing” element was not
discovered until 1886.
Imagine you are a chemist living in 1880. Study the section of the periodic table shown below as well as
the accompanying table of properties. (Scientists in 1880 hadn’t learned what atomic numbers are. They
also used “bonding power” to describe the number of chemical bonds an element could form.)
Si
Atomic mass
Ga
28
As
“Ekasilicon”
?
70
75
Sn
119
Some Properties of Selected Elements
Element
Color
Atomic Mass
Bonding Power
Silicon
steel gray
28
4
Gallium*
gray-black
70
3
“Ekasilicon”
?
?
?
Arsenic
Tin
silver to gray-black
gray-white
75
119
3
4
*One of Mendeleev’s original “missing elements,” which was discovered in 1875.
1. Which elements would you use to predict the properties of
“ekasilicon”? Why?
2. What color would you expect “ekasilicon” to be?
3. How many chemical bonds would you expect “ekasilicon” to form?
4. What atomic mass would you expect “ekasilicon” to have? Why?
87F
Name
Date
Class
Organizing the Elements
If the statement is true, write true. If the statement is false, change the underlined word
or words to make the statement true.
Mendeleev arranged his periodic table in order of increasing
1.
atomic number.
The rows in the periodic table are called periods.
2.
3.
Moving across the periodic table from left to right, one finds,
in order, metals, then gases, then nonmetals.
Another name for a period is a family.
4.
On the periodic table, elements in the same column have
5.
similar properties.
Fill in the blank to complete each statement.
6. An element’s table.
can be predicted from its location on the periodic
7. The average mass of all the isotopes of an element is called the
.
8. The modern periodic table is arranged in order of increasing
.
9. Information found on the periodic table for each element includes its atomic number,
, name, and atomic mass.
10. An element with atomic number 10 is located to the
element with atomic number 9.
87G
of an
Name
Date
Metals
What Are the Properties of Metals?
1a. EXPLAIN What does the term thermal conductivity mean?
b. INFER What property of metals led to the use of plastic or wooden
handles on many metal cooking utensils? Explain
I get it! Now I know that the physical properties of metals include
I need extra help with
How Are Metals Classified?
2a. IDENTIFY Which family of elements in the periodic table contains the
most reactive metals?
b. INFER Period 4 of the periodic table contains the elements
potassium, calcium, and copper. Which is the least reactive?
c. APPLY CONCEPTS How is plutonium made?
I get it! Now I know that metals are classified in the periodic table as
I need extra help with
95B
Class
Name
Date
Class
Metals
On a separate sheet of paper, identify the properties of metals and describe their position
in the periodic table.
95C
Name
Date
Class
Metals
Understanding Main Ideas
Answer the following questions in the spaces provided. Use a separate sheet of paper if
you need more room. Use a periodic table for reference.
1. What physical properties are shared by most metals?
2. Sodium (Na) and calcium (Ca) are in different families of metals.
Name the families of metals in which they belong, and describe each
family’s characteristics.
3. Would a metal in Group 13 be more or less reactive than a metal in
Group 1? Explain.
4. In what periods are the lanthanides and actinides? Where are they
placed in the periodic table? Why?
Building Vocabulary
Fill in the blank to complete each statement.
5. The reaction of a metal with oxygen to form rust is called
6. A material that is
shapes.
.
can be hammered into thin sheets and other
7. The ability to transmit heat or electricity to other objects is called
.
8. A material that is
can be drawn into a wire.
is the ease and speed with which an element combines with
9.
other substances.
95D
Name
Date
Class
Metals
Read the passage and look at the tables below it. Then use a separate sheet of paper to
answer the questions that follow the tables.
More Properties of Metals
You have learned that elements in the same group of the periodic table have similar properties. For
example, the metals of Group 1 are so reactive they do not exist uncombined in nature. The Group 2
metals are also quite reactive.
The tables below show the atomic radius and reactivity of most of the metals in Groups 1 and 2. The
more reactive a metal is, the more stars appear in the reactivity column. The tables also give the atomic
radius of these elements. You might expect the atomic radius of an element to be half its diameter.
However, atoms do not have a definite surface, as a ball does. An atom’s electrons are constantly moving
around the nucleus in a region of space that has no distinct edge. So, atomic radius is calculated as one
half the distance between the nuclei of two identical atoms. The unit of measurement is the picometer
(pm). One picometer is equal to 0.000000000001 meter.
Group 1
Group 2
Period
Element
2
Li
3
Atomic
Radius
(pm)
Reactivity
Rating
Atomic
Radius
(pm)
Period
Element
123
2
Be
89
Na
157
3
Mg
136
4
K
203
4
Ca
174
5
Rb
216
5
Sr
191
6
Cs
235
6
Ba
198
1. How does the atomic radius change from top to bottom in Groups 1
and 2?
2. How does the atomic radius change from left to right in Groups 1
and 2?
3. How does reactivity change from top to bottom in Group 1? Does the
same pattern hold in Group 2?
4. How does reactivity change from left to right in Groups 1 and 2?
5. What seems to be the relationship between atomic radius and the
reactivity of the elements in Group 1 and Group 2?
6. Francium is the Group 1 element of Period 7 and below cesium in
the periodic table. Infer how francium’s atomic radius compares
to cesium’s. Do you think francium is more or less reactive than
cesium? Explain.
95E
Reactivity
Rating
Name
Date
Class
Metals
Write the letter of the correct answer on the line at the left.
1.
If a material can easily be drawn into
the shape of a wire, it is
A ductile
B magnetic
C malleable
D reactive
2.
Which of the following is NOT a
characteristic of most metals?
A brittle
B good conductor
C ductile
D malleable
3.
The metals of Group 1 are commonly
called the
A transition metals
B alkaline earth metals
C lanthanides
D alkali metals
4.
One metal that is a liquid at room
temperature is
A magnesium
B manganese
C mercury
D sodium
Fill in the blank to complete each statement.
5. Gold, which is in Group 11 on the periodic table, is an example of a(n)
metal.
6. The family in the periodic table that contains the most reactive metals is the
metals.
are devices that move atomic nuclei at
7.
extremely high speeds.
8. Elements with atomic numbers above 95 are called
9. Thermal conductivity is the ability of an element to transfer
10. Reactivity is a(n)
property of metals.
95F
elements.
.
Name
Date
Nonmetals and Metalloids
What Are the Properties of Nonmetals?
1a. IDENTIFY What property of nonmetals is the opposite of malleable
and ductile?
b. MAKE GENERALIZATIONS What happens to the atoms of most
nonmetals when they react with other elements?
I get it! Now I know that the physical properties of nonmetals include
I need extra help with
What Are the Families Containing Nonmetals?
2a. LIST What are the nonmetals in Group 16 of the periodic table?
b. COMPARE AND CONTRAST How do the chemical properties of the
halogens compare to those of the noble gases?
c. ANSWER
How is the periodic table organized?
I get it! Now I know that the families containing nonmetals include
I need extra help with
105B
Class
Name
Date
Class
Nonmetals and Metalloids
On a separate sheet of paper, describe the physical and chemical properties of nonmetals.
105C
Name
Date
Class
Nonmetals and Metalloids
Understanding Main Ideas
Complete the following table. Use a periodic table for reference.
Element
Metal, Metalloid, or Nonmetal
Family Name
Arsenic
metalloid
1.
Sulfur
2.
oxygen family
Tin
metal
3.
Neon
4.
noble gas
Chlorine
nonmetal
5.
Silicon
6.
carbon family
7. Where in the periodic table are the nonmetals located? Where are
the metalloids?
Building Vocabulary
Fill in the blank to complete each statement.
8. A(n)
9. The
is formed of two atoms.
are a family of very reactive elements.
10. A type of element that has some of the properties of metals and some of nonmetals is
called a(n)
.
11. The
are a family of unreactive elements.
12. A(n)
is a type of element whose physical properties are
generally opposite to those of metals.
13. A substance that carries electricity under certain circumstances, but not under other
circumstances is called a(n)
.
105D
Name
Date
Class
Nonmetals and Metalloids
Read the passage and look at the table below it. Then use a separate sheet of paper to
answer the questions that follow the table. You may refer to the periodic table.
Nonmetals in the Atmosphere
On Earth, most nonmetals are found in their uncombined state in the atmosphere. In addition, some
nonmetals combine with other nonmetals to form important compounds in the atmosphere. Some of
the gases in the atmosphere support life on the planet in one way or another. Others, in great enough
concentration, can be dangerous to living things.
Composition of Earth’s Atmosphere
Component
Percent in Air
at Sea Level
Relationship to Living Things
Nitrogen (N2)
76.08
Used by bacteria to produce substances plants can
absorb as nutrients; part of all proteins
Oxygen (O2)
20.95
Required for respiration, a process in living things
that releases energy
Water (H2O)
1.0 (avg.)
Essential to life as we know it
Argon (Ar)
0.93
None known
Carbon dioxide
(CO2)
0.032
Needed by plants to produce their own food
through photosynthesis
Neon (Ne)
0.001
None known
Helium (He)
0.0005
None known
Nitrous Oxide
(N2O)
0.00003
Commonly used as a dental anesthetic but has no
effect in concentrations found in the air
Carbon monoxide
(CO)
0.00001
Poisonous gas produced in part by the burning of
fossil fuels
1. Based on this table, what do the Group 18 elements have in
common?
2. Which substances are combinations of nonmetals?
3. Which nonmetals in the atmosphere and their combinations are
essential to life on Earth?
4. Which are the four most abundant components of the atmosphere?
Taken together, about what percent of the atmosphere do those four
components make up?
105E
Name
Date
Class
Nonmetals and Metalloids
Write the letter of the correct answer on the line at the left.
1.
3.
Which of the following is NOT a
property of most nonmetals?
A found on the right side of the
periodic table
B solids tend to be dull and brittle
C excellent electric conductivity
D many are gases at room temperature
2.
Two of the same atoms bonded
together is called a(n)
A isotope
B diatomic molecule
C binary atom
D semiconductor
4.
A
B
C
D
The only nonmetal in Group 14 is
carbon
oxygen
nitrogen
fluorine
The highly reactive nonmetals of
Group 17 are called the
A noble gases
B metalloids
C halogens
D actinides
If the statement is true, write true. If the statement is false, change the underlined word
or words to make the statement true.
Atoms of nonmetals usually lose electrons when they combine
5.
with other atoms.
When two or more atoms bond by sharing electrons, they form
6.
a molecule.
7.
The elements that have some properties of metals and some
properties of nonmetals are called halogens.
8.
Helium has chemical properties so different from those of the
other elements that it cannot be placed in any group.
9.
Substances that can carry electric current under some
conditions but not under others are called semiconductors.
The Group 15 element oxygen is used to make compounds
10.
known as fertilizers.
105F
Name
Date
Class
Radioactive Elements
What Happens to an Atom During Radioactive Decay?
1a. DEFINE The spontaneous emission of radiation by an unstable atomic
nucleus is called
b. APPLY CONCEPTS What caused the fogging of the photographic plates
that Becquerel observed in 1896?
I get it! Now I know that during radioactive decay
I need extra help with
What Does Radioactive Decay Produce?
2a. IDENTIFY What is the name of the particle produced by radioactive
decay that consists of 2 protons and 2 neutrons?
b. COMPARE AND CONTRAST Rank the three major types of nuclear
radiation from 1 (most penetrating) to 3 (least penetrating).
Alpha
Beta
Gamma
c. PREDICT What is the identity and mass number of the nucleus formed
during the beta decay of magnesium-28?
I get it! Now I know that the three major forms of radiation produced during radioactive
decay are
I need extra help with
113B
Name
Date
Radioactive Elements
How Are Radioactive Isotopes Useful?
3a. EXPLAIN Why is half-life useful to an archaeologist?
b. RELATE CAUSE AND EFFECT Why are radioactive isotopes that emit
gamma rays useful for treating some forms of cancer?
I get it! Now I know that four uses for radioactive isotopes are
I need extra help with
113C
Class
Name
Date
Class
Radioactive Elements
On a separate sheet of paper, define radioactive decay, describe its products, and
summarize its uses.
113D
Name
Date
Class
Radioactive Elements
Understanding Main Ideas
Look at the diagrams below. Label each diagram with the type of radioactive decay
it illustrates.
1.
2.
3.
Building Vocabulary
Fill in the blank to complete each statement.
4. Scientists use the amount of radioactive isotopes found in rocks and fossils to
calculate their ages. This process is called
5. A(n)
neutrons and is positively charged.
consists of two protons and two
6. A(n)
involves the particles found in
the nucleus of an atom. It changes one element into another element.
consists of high-energy waves and
7.
always accompanies alpha and beta decay.
8. The spontaneous emission of radiation by an unstable atomic nucleus is
called
.
9. A(n)
problems.
can be used by doctors and by industry to diagnose
10. A(n)
off by a nucleus during radioactive decay.
is a fast-moving electron given
11. Half of the radioactive atoms in a sample of sodium-24 will decay in 15 hours.
Fifteen hours is the
of sodium-24.
113E
.
Name
Date
Class
Radioactive Elements
Read the passage. Then use a separate sheet of paper to answer the questions that
follow.
Radon Gas
Radon is a radioactive element that is formed from the radioactive decay of uranium-238. Radon-222
is the most common isotope of this element. Its half-life is 3.8 days. Radon is a colorless, odorless,
tasteless gas.
Because uranium-238 is fairly rare, so is radon gas. Uranium-238 is found under Earth’s surface in some
types of rocks. When radon is formed, it tends to rise up to the surface. Because radon is much more
dense than air, it tends to stay very close to the ground. As a result, it sometimes builds up in the lower
levels of houses, especially in underground areas such as basements.
Being exposed to high levels of radon gas over a period of time can increase a person’s chances of
developing lung cancer. The level of radon gas in a home can be measured with a testing kit. If radon is
found, there are several methods of preventing more of it from entering a house. One method is called
soil suction. Soil suction involves pulling the radon gas from the soil below the house and into a pipe.
The pipe releases the gas away from the house. Other methods involve increasing the movement of
fresh air through the house or sealing cracks through which radon gas can enter.
1. If there is almost no uranium in the area where someone lives, should
that person be concerned about radon gas in his or her home? Why
or why not?
2. Should someone who lives on the sixth floor of an apartment
building be concerned about radon in his or her apartment? Why
or why not?
3. Do you think radon would be more of a health hazard if it were
a solid instead of a gas? Explain.
4. The diagram below shows how uranium-238 decays to radon-222.
For each step in this process, fill in the blank to indicate whether an
alpha particle or a beta particle is produced. The first step has been
done for you.
uranium-238
thorium-234
alpha particle
radium-226
d.
thorium-230
c.
protactinium-234
a.
uranium-234
b.
radon-222
e.
113F
Name
Date
Class
Radioactive Elements
Write the letter of the correct answer on the line at the left.
1.
Radioactive isotopes that can be
followed through the steps of a chemical
reaction or industrial process are called
A transformers
B tracers
C gamma rays
D reactants
2.
Which statement is NOT true of
radioactive decay?
A It involves the nucleus of an atom.
B It involves radioactive isotopes.
C The identity of the atom remains the same.
D Fast moving particles and energy are
released.
3.
Alpha and beta decay are almost
always accompanied by
A gamma radiation
B an increase in atomic number
C a decrease in atomic number
D a catalyst
4.
In relation to the original atom, the
atom that results from beta decay has an
atomic number that is
A 1 less
B 1 more
C 2 less
D the same
If the statement is true, write true. If the statement is false, change the underlined word
or words to make the statement true.
Uranium was the radioactive element studied by Becquerel and
5.
the Curies.
The most penetrating type of nuclear radiation is the
6.
alpha particle.
7.
The half-life of cobalt-60 is 5.26 years. After 10.52 years,
5 grams of a 20-gram sample will remain.
During radioactive decay, the identity of an atom remains
8.
the same.
Alpha particles are fast-moving electrons given off during
9.
radioactive decay.
Chemical reactions involve the protons and neutrons in the
10.
nucleus of an atom.
113G
Name
Date
Class
Atoms, Bonding, and the Periodic Table
What Determines an Element’s Chemistry?
1a. DEFINE What are valence electrons?
b. EXPLAIN Why do the properties of elements change in
a regular way across a period?
c. RELATE CAUSE AND EFFECT Explain the reactivity of the noble gases in
terms of valence electrons.
I get it! Now I know that the chemical properties of an element are determined
by
I need extra help with
129B
Name
Date
Class
Atoms, Bonding, and the Periodic Table
On a separate sheet of paper, use the periodic table to create electron dot diagrams
for barium (Ba), carbon (C), cesium (Cs), iodine (I), krypton (Kr), phosphorous (P), and
strontium (Sr).
129C
Name
Date
Class
Atoms, Bonding, and the Periodic Table
Understanding Main Ideas
Look at the diagram below. Then answer the following questions in the space provided.
1. How many protons does a nitrogen atom have?
2. How many valence electrons does a nitrogen atom have?
3. Is nitrogen reactive or stable?
4. Neon (Ne), which has an atomic number of 10 is in Group 18 in the periodic table. To which
group does nitrogen belong?
5. The element directly below nitrogen in the periodic table is phosphorous (P). How many
valence electrons does phosphorous have?
6. Will the properties of nitrogen be more similar to the properties of neon or the properties
of phosphorous? Explain.
Building Vocabulary
If the statement is true, write true. If the statement is false, change the underlined word
or words to make the statement true.
7.
An element’s reactivity is determined by the
number of protons found in an atom of the element.
8.
The force of attraction that holds two atoms
together is called a chemical bond.
9.
In a(n) periodic table, dots around an
element’s symbol indicate the number of valence electrons in
an atom.
129D
Name
Date
Class
Atoms, Bonding, and the Periodic Table
Read the passage, look at the diagram, and study the table. Then use a separate sheet of
paper to answer the questions that follow.
The Rockets’ Red Glare
The basic fireworks unit is called a shell,
and it is packed with chemicals that produce
light, smoke, and noise when they burn.
The effects depend on which chemicals
are packed into the shell and how they are
arranged.
A simple shell is shown at the right. When
the gunpowder is at the bottom of the shell
is lit, it explodes and lifts the shell into the air.
By the time the shell has reached the high point of its path, a second fuse ignites the other chemicals.
Some shells explode all at once. Others are made of smaller shells that burst apart and explode
separately. Time delays can be used to make a shell explode in stages.
The table below lists some chemicals and the effects they produce.
Element
Effect
strontium or lithium
red color
barium
green color
copper
blue color
sodium
yellow color
magnesium or aluminum
white color
potassium or sodium
whistling sound
potassium and sulfur
white smoke
1. To which groups of the periodic table do the majority of the
elements listed in the table above belong? Why do you think
elements in these groups are used in making fireworks?
2. Which group of elements could you not use in making fireworks?
Explain your answer.
3. Why would you want to have two or more separate fuses in a rocket?
4. Solutions of magnesium, barium, and strontium are clear and
colorless. Predict what might happen if a drop of each solution was
held in the flame of a lab burner.
129E
Name
Date
Class
Atoms, Bonding, and the Periodic Table
If the statement is true, write true. If the statement is false, change the underlined word
or words to make the statement true.
An atom’s valence electrons are those electrons that have the
1.
highest energy.
Atoms tend to be stable and nonreactive if they have six
2.
valence electrons.
3.
In the periodic table, the number of valence electrons in each
element decreases from left to right across each period.
The reactivity of a metal depends on how easily it loses its
4.
valence electrons.
5.
Within each period in the periodic table, elements have similar
properties because they have the same number of valence electrons.
Fill in the blank to complete each statement.
6. The number of
determines its chemical properties.
in the atom of an element
7. The columns in the periodic table are called
.
8. A(n)
electrons in an atom in pictorial fashion.
shows the number of valence
9. The attractive force that holds two atoms together is called a(n)
.
10. Because it can either lose or share electrons when it combines with other elements,
each
has some of the properties of metals and some of the
properties of nonmetals.
129F
Name
Date
Class
Ionic Bonds
How Do Ions Form?
1a. REVIEW An atom that loses a valence electron becomes a (positive/
negative) ion. An atom that gains a valence electron becomes a
(positive/negative) ion.
b. APPLY CONCEPTS Write the symbols for the ions that form when
potassium and iodine react to form the ionic compound potassium
iodide.
c. RELATE CAUSE AND EFFECT Why is potassium iodide electrically neutral?
I get it! Now I know ions form when
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How Are the Formulas and Names of Ionic Compounds Written?
2a. EXPLAIN The formula for sodium sulfide is Na2S. Explain what this
formula means.
b. APPLY CONCEPTS Write the formula for calcium chloride. Explain how
you determined this formula.
I get it! Now I know that to write the formula for an ionic compound,
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137B
Name
Date
Ionic Bonds
What Are Properties of Ionic Compounds?
3a. REVIEW Ionic bonds are strong enough to cause all ionic compounds
to be
at room temperature.
b. RELATE CAUSE AND EFFECT Solid table salt does not conduct electric
current. How does dissolving salt in water allow electric current to
flow?
I get it! Now I know that properties of ionic compounds include
I need extra help with
137C
Class
Name
Date
Class
Ionic Bonds
A fluorine (F) ion has a charge of 1–. An aluminum (Al) ion has a charge of 3+. On a
separate sheet of paper, explain how fluorine and aluminum would exchange valence
electrons to form an ionic compound. Then write the compound’s chemical formula and
name the compound.
137D
Name
Date
Class
Ionic Bonds
Understanding Main Ideas
Fill in the blank to complete each statement.
1. Negative ions form when atoms
valence electrons.
2. In the formation of an ionic compound, a metal atom is most likely to
valence electrons.
3. Ionic compounds form because
attract.
charges
Answer the following questions in the spaces provided. You may use a periodic table.
4. A potassium ion has a charge of 1+. A sulfide ion has a charge of 2−.
What is the chemical formula for potassium sulfide?
5. Name the following compound: MgO.
Building Vocabulary
Write a definition for each of these terms on a separate piece of paper.
6. ion
7. polyatomic ion
8. ionic bond
9. ionic compound
10. chemical formula
137E
Name
Date
Class
Ionic Bonds
Read the passage and look at the diagram to its right. Then use a separate sheet of
paper to answer the questions that follow.
Pulling Away Electrons
You know that the metals in Group 1 and 2 are quite reactive. They combine
easily with certain other elements to form compounds. Atoms from Group 1 react
by losing one electron; atoms from Group 2 lose two electrons. It takes energy to
remove an electron from an atom. Some atoms hold their electrons tighter than
other atoms do. Also, an individual atom holds some of its electrons tighter than
other electrons.
The size of an atom’s radius affects how tightly it holds its electrons. The larger
the radius of an atom, the farther away from the nucleus some of its electrons
are. The electron held the least tightly is easiest to remove. To remove yet
another electron requires more energy than was needed to remove the first.
The figure below compares the atomic radii of the elements in Groups 1 and 2.
The number underneath each element represents the atomic radius measured
in picometers (pm).
1. What do you notice about atomic radius as you look down a group?
As you look across a period from Group 1 to Group 2?
2. Which element would you expect to be the most reactive in Group 1?
In Group 2? Explain your answer.
3. Within each period, which element of the two groups would you
expect to be more reactive? Explain your answer.
4. Across the periodic table, atomic radius continues to decrease
through Group 17. How does this fact help explain why the
metals in Groups 3 through 13 are less reactive than the metals
in Group 1 and 2?
137F
Name
Date
Class
Ionic Bonds
Write the letter of the correct answer on the line at the left.
1.
Ionic bonds form between two ions that
have
A ionic compounds
B negative charges
C positive charges
D opposite charges
2.
Ions that are made of more than
one atom are called
A ionic compounds
B crystals
C polyatomic atoms
D ionic bonds
3.
Which is most likely to form a negative
ion?
A an element from Group 17
B a metal
C an element from Group 1
D an element with atoms that have eight
valence electrons
4.
Which of the following is the
correct name for MgCl2?
A magnesium chlorine
B magnesium dichlorine
C magnesium chloride
D magnesium dichloride
Fill in the blank to complete each statement.
5. A(n)
is an atom or group of atoms that has an electric charge.
6. The attraction between oppositely charged ions is called a(n)
.
7. When an atom loses a valence electron, it becomes a(n)
ion.
8. In order to have a stable arrangement of 8 valence electrons, metal atoms are likely
to
electrons.
9. In an ionic compound, the total positive charge of all the positive ions
the total negative charge of all the negative ions.
10. Because the force of attraction between the positive and negative ions is so strong,
ionic compounds have
melting points.
137G
Name
Date
Class
Covalent Bonds
How Are Atoms Held Together in a Covalent Bond?
I get it! Now I know that the atoms in a covalent bond are held together by
I need extra help with
What Are Properties of Molecular Compounds?
I get it! Now I know that properties of molecular compounds include
I need extra help with
145B
Name
Date
Class
Covalent Bonds
How Do Bonded Atoms Become Partially Charged?
1a. REVIEW What type of bonds are formed when atoms share electrons
unequally?
b. PREDICT Would carbon dioxide or water have a higher boiling point?
Explain.
c. ANSWER
How can bonding determine the properties of a substance?
I get it! Now I know that some atoms in covalent bonds become slightly negative or slightly
positive when
I need extra help with
145C
Name
Date
Class
Covalent Bonds
On a separate sheet of paper, compare and contrast carbon dioxide and water. Be sure to
fully describe the types of bonds involved, and compare and contrast the properties of
the compounds.
145D
Name
Date
Class
Covalent Bonds
Understanding Main Ideas
Answer the following questions in the spaces provided. Use the diagram at right to
answer questions 1–5.
1. Circle all of the covalent bonds in the electron dot diagrams.
2. Which bond(s) shown are double bonds?
3. Which bond(s) shown are triple bonds?
4. Which molecule(s) shown have polar bonds?
5. Compare and contrast O2 and F2.
Building Vocabulary
Match each term with its definition by writing the letter of the correct definition in the
right column on the line beside the term in the left column.
6.
molecule
7.
double bond
8.
nonpolar bond
9.
polar bond
d. a bond in which electrons are shared equally
covalent bond
e. a bond in which four electrons are shared
10.
a. the chemical bond formed when two atoms share
electrons
b. a neutral group of atoms joined by covalent bonds
c. a bond in which electrons are shared unequally
145E
Name
Date
Class
Covalent Bonds
Read the passage and look at the diagrams next to it. Then use a separate sheet of paper
to answer the questions that follow the passage.
Oil Spills
Each year over 907,000 metric tons of crude oil are spilled in Earth’s oceans. This is enough oil to fill
100 school gymnasiums! It is important to clean up crude oil as soon after a spill as possible, because
spilled crude oil has negative effects on the environment. Oil on ocean surfaces is harmful to ocean life
because it blocks sunlight and reduces the level of dissolved oxygen in the water. In addition, many birds
and fish die from contact with crude oil because the oil damages feathers and gills.
Two methods used to clean up oils spills are
1. A floating barrier is placed around the spill to keep
it from spreading. Because oil floats on water,
the oil can be skimmed off the top of the water.
Skimming the top of the water using a net with
extremely small holes allows the water to escape
but not the oil.
2. Chemicals that act like detergents
are sprayed onto the surface of
the spill. These chemicals break up
the oil into tiny droplets. The small
particles of oil spread over a large
area have less effect on marine life
than larger particles.
Both of these methods work because of
the chemical properties of oil molecules.
Oil molecules are nonpolar, so they will not
mix with polar water molecules. Detergents
are long molecules that have a polar end
and a nonpolar end, like the molecule shown in Figure 1. The polar end of the detergent attracts water
molecules, and the nonpolar end attracts oil molecules. Figure 2 shows how detergent molecules cause
the formation of droplets of water, detergent, and oil molecules.
1. Explain how the nonpolar character of oil molecules helps when
removing oil from water using nets and floats barriers.
2. The long “tail” on a detergent molecule is made up mostly of carbon
atoms bonded to other carbon atoms. Why would you expect the tail
to be nonpolar?
3. How does detergent sprayed on an oil spill break up the spill?
145F
Name
Date
Class
Covalent Bonds
Write the letter of the correct answer on the line at the left.
1.
In an electron dot diagram, two pairs of
shared electrons represents a
A single bond
B double bond
C triple bond
D quadruple bond
2.
A nitrogen molecule (N2) has one
triple bond. How many electrons do the
nitrogen atoms share?
A 1
B 3
C 4
D 6
3.
Compared to ionic compounds,
molecular compounds generally have
A good conductivity
B greater densities
C more chemical bonds
D a low boiling point
4.
Compared to ionic compounds,
molecular compounds generally have
A stronger chemical bonds
B poor conductivity
C a high melting point
D lower densities
If the statement is true, write true. If the statement is false, change the underlined word
or words to make the statement true.
The chemical bond formed when two atoms share electrons is
5.
called a(n) ionic bond.
Covalent bonds usually form when a nonmetal combines with
6.
a(n) metal.
A(n) ion is a neutral group of atoms joined by covalent bonds.
7.
If a molecule contains polar bonds, the molecule may or may
8.
not be polar overall.
9.
In a(n) polar bond, one atom pulls on the shared electrons
more than the other atom.
The forces between molecules are much stronger than the
10.
forces between ions.
145G
Name
Date
Bonding in Metals
What Is the Structure of a Metal Crystal?
I get it! Now I know that a metal crystal consists of
I need extra help with
What Are Properties of Metals?
1a. IDENTIFY What accounts for the properties of metals?
b. EXPLAIN Explain why metals are good conductors of electric current.
c. APPLY CONCEPTS Why is it safer to use a nonmetal mixing spoon when
cooking something on a hot stove?
I get it! Now I know that properties of metals include
I need extra help with
151B
Class
Name
Date
Class
Bonding in Metals
On a separate sheet of paper, explain how the behavior of valence electrons contributes
to the following properties of metals: luster, malleability, ductility, high electrical
conductivity, and high thermal conductivity.
151C
Name
Date
Class
Bonding in Metals
Understanding Main Ideas
Use the diagram to answer the following questions on a separate sheet of paper.
1. What do points a and b represent?
2. What action is modeled by the diagram? Explain.
3. How does metallic bonding explain the result at point c?
Match each property of metal with its description by writing the letter of the correct
description in the right column on the line beside the property in the left column.
4.
luster
a. easily beaten into complex shapes
5.
ductility
b. conducts electric current well
6.
malleability
c. shiny and reflective
7.
thermal conductivity
d. easily bent and pulled into thin strands
8.
electrical conductivity
e. conducts heat well
Building Vocabulary
On a separate sheet of paper, write a definition for each of these terms.
9. metallic bond
10. alloy
151D
Name
Date
Class
Bonding in Metals
Read the passage and look at the table below it. Then use a separate sheet of paper to
answer the questions that follow the table.
How Hard?
Some metals, such as copper and gold, are also minerals. A mineral is a naturally occurring solid that
has a crystal structure and a definite chemical composition. Their crystal structure makes minerals hard.
Nonetheless, there is considerable variation among minerals in hardness. Talc is the softest mineral, and
diamond is the hardest. Mohs Scale of Hardness, which is shown below, is used to classify minerals and
other substances according to their hardnesses. An object on the scale will scratch anything with a lower
number, but will be scratched by anything with a higher number. The table includes some everyday
objects in parentheses for comparison.
Mineral (Object)
Hardness
Mineral (Object)
Hardness
talc
1
(knife blade)
5.5
(asphalt)
1.3
feldspar
6
gypsum
2
(steel file)
6.5
(fingernail)
2.5
quartz
7
calcite
3
topaz
8
(copper coin)
3
corundum
9
fluorite
4
diamond
10
apatite
5
1. Which minerals will scratch quartz? How do you know?
2. According to the information in the table, do you think that you
could scratch a copper coin with a knife blade? Explain your answer.
3. How could you determine the hardness rating for a mineral not listed
on the scale?
151E
Name
Date
Class
Bonding in Metals
Write the letter of the correct answer on the line at the left.
1.
3.
Why are alloys generally used to make
everyday objects?
A Alloys are often stronger and less reactive
than pure metals.
B Alloys have higher melting points than pure
metals.
C Alloys are less expensive to produce than
pure metals.
D Alloys have ionic bonds instead of metallic
bonds.
2.
Which of the following is NOT a
property of metals?
A ductile
B good electrical conductor
C good thermal insulator
D malleable
4.
A
B
C
D
Metallic bonding is
a type of covalent bond
a type of ionic bond
an attraction between positive and
negative ions
an attraction between positive ions and
electrons
At room temperature, most metals
are
A liquid
B solid
C gas
D an alloy
Fill in the blank to complete each statement.
5. An attraction between a positive metal ion and surrounding electrons is
a(n)
bond.
6. Metals typically have
melting points.
7. The metal fins that cool a motorcycle’s engine make use of the high
conductivity of metals.
8. Metals are often used to make wire because they are
9. Metals are used in electrical wires because they have high
conductivity.
10. Nonmetals are unlikely to form metallic bonds because their
are strongly held.
151F
.
Name
Date
Class
Observing Chemical Change
How Can Changes in Matter Be Described?
1a. REVIEW The freezing point of water is a (physical/chemical) property. The ability
of oxygen to react with iron to cause rust is a (physical/chemical) property.
b. POSE QUESTIONS When silver coins are found in ancient shipwrecks, they are coated
with a black crust. Ask a question that could help you determine whether the silver
underwent a chemical change or a physical change. Explain.
I get it! Now I know that two ways changes in matter can be described are
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How Do You Identify a Chemical Reaction?
2a. LIST What changes in physical properties can be used as evidence that
a chemical reaction has occurred?
b. APPLY CONCEPTS What evidence of a chemical change is observed
when rust forms on iron?
c. COMPARE AND CONTRAST How are endothermic and exothermic
reactions the same? How are they different?
I get it! Now I know that two kinds of changes you can observe when chemical reactions
occur are
I need extra help with
169B
Name
Date
Class
Observing Chemical Change
On a separate sheet of paper, describe what happens when reactants form products.
169C
Name
Date
Class
Observing Chemical Change
Understanding Main Ideas
Complete the following table. Describe changes in properties that you might notice
during each process and state whether the changes are chemical or physical.
Changes in Matter
Event
Observable Changes
Type of Change
Baking a cake
1.
2.
Burning a log
3.
4.
Freezing water
5.
6.
Building Vocabulary
Fill in the blank to complete each statement.
7. Any change that alters a substance without changing it into another
substance is a(n)
change.
8.
is anything that has mass and takes up space.
9. A reaction that releases energy in the form of heat is called a(n)
reaction.
10. A(n)
absorbed.
reaction is a reaction in which energy is
11. A chemical change is also referred to as a(n)
.
12. A(n)
is a solid formed from liquid reactants
during a chemical reaction.
169D
Name
Date
Class
Observing Chemical Change
The figures show methods for separating mixtures. Read the passage and study the
figures. Then answer the questions that follow on a separate sheet of paper.
Separation Science
A mixture is a combination of two or more pure substances in which the substances do not combine
to form new material. Therefore, you should be able to separate a mixture into the substances that
make it. There are several ways to separate mixtures. Figure 1 shows a mixture of sand and water being
separated by filtration. The salt in a solution of salt water can be separated by evaporation, shown
in Figure 2. When you let the sand particles in a mixture of sand and water settle to the bottom of a
container, you are using a method called decanting, shown in Figure 3.
1. Using Figure 1, explain the process of filtration. Give another
example of filtration used to separate a mixture.
2. Discuss a use for evaporation.
3. What types of mixtures could be separated by decanting? Is
laboratory equipment necessary for decanting a mixture? Why or
why not?
4. Would a separation of the types described above cause a chemical
change or a physical change? Explain your answer.
169E
Name
Date
Class
Observing Chemical Change
Write the letter of the correct answer on the line at the left.
1.
3.
Which of the following is true about
chemical reactions?
A They are accompanied by changes in
energy.
B They form new substances with new
properties.
C both A and B
D neither A nor B
2.
Which of the following is NOT a
physical property?
A melting point
B state of matter
C density
D flammability
4.
A
B
C
D
In an endothermic reaction, energy is
absorbed
released
converted to mass
synthesized
Substances formed as a result of a
chemical reaction are called
A catalysts
B precipitates
C products
D reactants
If the statement is true, write true. If the statement is false, change the underlined word
or words to make the statement true.
In an exothermic reaction, products have more energy than
5.
reactants.
Water boils at 100°C. This is an example of a chemical property.
6.
Substances that enter into a chemical reaction are called
7.
products.
The ability to react with oxygen is an example of a chemical
8.
property.
9.
10.
Another name for a chemical change is a chemical bond.
In a physical change, some of the physical properties of the
substance may be altered and the chemical composition remains the same.
169F
Name
Date
Class
Describing Chemical Reactions
What Information Does a Chemical Equation Contain?
1a. EXPLAIN What do the formulas, arrows, and plus signs tell you in
a chemical equation?
b. INTERPRET DATA Write the chemical equation for the following
reaction: The elements sodium and chlorine combine to yield the
compound sodium chloride.
I get it! Now I know that a chemical equation tells you
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How Is Mass Conserved During a Chemical Reaction?
2a. INFER If the total mass of the products in a reaction is 90 grams,
what was the total mass of the reactants?
b. APPLY CONCEPTS Balance the equations.
• Al + CuO → Al2O3 + Cu
• Fe2O3 + C → Fe + CO2
• SO2 + O2 → SO3
181B
Name
c. ANSWER
Date
Class
How is matter conserved in a chemical reaction?
I get it! Now I know that the mass of reactants and products
I need extra help with
Describing Chemical Reactions
What Are Three Types of Chemical Reactions?
3a. CLASSIFY What type of chemical reaction is shown in the chemical equation below?
Zn + 2 HCl → H2 + ZnCl2
b. DRAW CONCLUSIONS The elements iron and oxygen can react to form
the compound iron oxide. What type of reaction is this? Explain.
I get it! Now I know that three types of chemical reactions are
I need extra help with
181C
Name
Date
Class
Describing Chemical Reactions
On a separate sheet of paper, identify the basic structure of a chemical equation, explain
why an equation must be balanced, and describe the three types of chemical reactions.
181D
Name
Date
Class
Describing Chemical Reactions
Understanding Main Ideas
Complete the table. Balance each equation. Then indicate whether the reaction is a
synthesis, decomposition, or replacement reaction.
Given Equation
Balanced Equation
Type of Reaction
1.
FeS + HCl → FeCl2 + H2S
a.
b.
2.
Na + F2 → NaF
a.
b.
3.
HgO → Hg + O2
a.
b.
Answer questions 4 and 5 on a separate sheet of paper.
4. Describe in words the reaction represented by the equation and
include a description of the composition of each kind of molecule.
2 H2 + O2 → 2 H2O
5. Use the law of conservation of mass to explain why the equation in
question 4 is balanced.
Building Vocabulary
Match each term with its definition by writing the letter of the correct definition in the
right column on the line beside the term in the left column.
6.
chemical equation
a. substance present after a reaction
7.
decomposition
reaction
8.
coefficient
c. principle that states that matter is not created or
destroyed during a chemical reaction
9.
product
d. reaction in which one element replaces another in a
compound
10.
reactant
e. substance present before a reaction
11.
synthesis reaction
f. number telling how many molecules of a substance are
involved in a chemical reaction
12.
replacement reaction
g. reaction in which compounds are broken down into
simpler substances
13.
conservation of mass
h. uses symbols and formulas to show chemical reactions
b. reaction in which substances combine to form a more
complex compound
181E
Name
Date
Class
Describing Chemical Reactions
Read the passage and study the figure. Then answer the questions that follow on a
separate sheet of paper.
The Decomposition of Water
You have learned that hydrogen gas and oxygen gas can react to produce water. The reverse of this
reaction can also occur. In other words, water can be broken down to make hydrogen gas and oxygen
gas. The breakdown of water is a decomposition reaction.
H2O
Water
→
+
H2
Hydrogen gas
O2
Oxygen gas
For this reaction to occur, there must be an electric current through the water as shown in the figure
below. Two wires are connected to a battery, and the free ends of the wires are put into a beaker of
water that contains a small amount of sulfuric acid. The sulfuric acid helps to increase the flow of current
through the water.
1. Write a balanced equation for the decomposition of water.
2. How many atoms of hydrogen are on the left side of the balanced
equation? How many oxygen atoms? How many hydrogen atoms
are on the right side of the balanced equation? How many oxygen
atoms?
3. The water in a beaker has a mass of 200 g. An electric current is
turned on in the water for two hours. Afterward the water has a
mass of only 176 g. What happened to the missing mass?
4. Looking at the figure above, how can you tell that a reaction is
occurring?
181F
Name
Date
Class
Describing Chemical Reactions
Write the letter of the correct answer on the line at the left.
In a balanced chemical equation,
atoms are conserved
coefficients are equal
molecules are equal
energy is not conserved
2.
When the equation Al + Br2 → AlBr3 is
balanced, the coefficient for Al is
A 1
B 2
C 3
D 4
The reaction in which hydrogen
and oxygen are produced by running
an electric current through water is an
example of
A single replacement
B decomposition
C synthesis
D double replacement
4.
A reaction that has two compounds
as reactants and two compounds as
products is most likely a
A synthesis reaction
B single replacement reaction
C double replacement reaction
D decomposition reaction
1.
A
B
C
D
3.
Fill in the blank to complete each statement.
5. A number written in front of a chemical formula is a(n)
.
6. The principle that states that matter is neither created nor destroyed during
a chemical reaction is called the law of
.
7. The production of carbon dioxide during the burning of a fuel is an example
of a(n)
reaction.
8. In a chemical equation, the arrow is read as
.
9. In the balanced chemical equation for the formation of ammonia (NH3) from
nitrogen (N2) and hydrogen (H2), the sum of the coefficients is
10. The law of conservation of mass was first demonstrated by the French
chemist
.
181G
.
Name
Date
Class
Controlling Chemical Reactions
How Do Reactions Get Started?
I get it! Now I know that in order for reactions to get started
I need extra help with
What Affects the Rate of a Chemical Reaction?
1a. DESCRIBE To slow down a reaction, you can (increase/decrease) the
concentration of the reactants.
b. COMPARE AND CONTRAST What would react more quickly in the air,
a pile of grain or a cloud of grain dust? Explain.
c. EXPLAIN How do enzymes speed up chemical reactions in your body?
I get it! Now I know that the rate of a chemical reaction can be affected by
I need extra help with
187B
Name
Date
Class
Controlling Chemical Reactions
On a separate sheet of paper, identify the relationship between activation energy and the
start of a chemical reaction. Then describe the factors that affect reaction rates.
187C
Name
Date
Class
Controlling Chemical Reactions
Understanding Main Ideas
Use the figures below to answer questions 1–3. Write your answers on a separate sheet
of paper.
1. Use what you know about endothermic and exothermic reactions to explain the
differences in the graphs above.
2. Why is the activation energy pictured as a hill in the two diagrams?
3. Explain how adding heat to the reactions shown in the diagram would change
the rate of these chemical reactions. Name two other ways to change the rate
of a chemical reaction.
Building Vocabulary
Write a definition for each of these terms on the lines below.
4. concentration
5. enzyme
6. inhibitor
187D
Name
Date
Class
Controlling Chemical Reactions
Read the passage and study the figure. Then answer the questions that follow on a
separate sheet of paper.
Flameless Ration Heaters
Suppose that you are a soldier on patrol far from your base camp. The weather is very cold and you
wish you had something warm to eat. However, you aren’t carrying a camp stove and it would be too
dangerous to light a fire because the smoke would reveal your position. Luckily, you have a Meal Ready
to Eat (MRE) and a Flameless Ration Heater (FRH) in your backpack. (A ration is a portion of food.)
An MRE is a meal, such as beef stew, inside a special pouch made of aluminum foil and plastic. To heat
your MRE, you slide it into an FRH, as shown in the figure. An FRH is a kind of plastic envelope that
contains certain chemicals. When you add water to the FRH, an exothermic reaction occurs. The heat
produced by this reaction warms up your meal in about 15 minutes.
The chemicals inside the FRH include magnesium (Mg), iron (Fe), and sodium chloride (NaCl). The
reaction that takes place when water is added to an FRH is as follows.
Mg
Magnesium
+
2 H2O
Water
→
Mg(HO)2
+
Magnesium hydroxide
H2
Hydrogen gas
The reaction of magnesium and water is normally very slow. As a result, it gives off heat very slowly.
In an FRH, however, this reaction occurs much faster and so it gives off heat much faster as well.
1. Iron and sodium chloride are present in an FRH, but they are not
reactants in the equation shown above. Why do you think they are
included in an FRH?
2. Why do you think an FRH does not come with water already in it?
3. Do you think there is one large piece of magnesium metal or many
small pieces of magnesium metal in an FRH? Explain.
4. Why is it important that the reaction in an FRH be fast?
187E
Name
Date
Class
Controlling Chemical Reactions
If the statement is true, write true. If the statement is false, change the underlined word
or words to make the statement true.
Increasing the surface area of the reactants will decrease
1.
the rate of the reaction.
2.
The amount of a substance in a given volume is the
concentration of the substance.
The effect of a catalyst on a reaction is to raise the
3.
activation energy.
4.
Only some reactions require activation energy.
5.
A(n) inhibitor decreases the rate of a reaction.
Fill in the blank to complete each statement.
6. The burning of fuels, such as coal, natural gas, or oil, involves a(n)
reaction.
7. In an endothermic reaction, the energy of the products is
the energy of the reactants.
8. Increasing the temperature of a reaction will
reaction.
than
the rate of the
9. The amount of a substance in a given volume is called
10. Biological catalysts in the human body are called
187F
.
.
Name
Date
Class
Understanding Solutions
How Are Mixtures Classified?
1a. REVIEW What is a solution?
b. COMPARE AND CONTRAST How are colloids and suspensions different
from solutions?
c. INFER Suppose you mix food coloring in water to make it
blue. Have you made a solution or a suspension? Explain.
I get it! Now I know that classifying mixtures as solutions, colloids, and suspensions is
based on
I need extra help with
How Does a Solution Form?
2. APPLY CONCEPTS Why is salt sprinkled on icy roads and sidewalks?
I get it! Now I know that in a solution, the particles of solute
I need extra help with
203B
Name
Date
Class
Understanding Solutions
On a separate sheet of paper, explain what a solution is and how one is formed.
203C
Name
Date
Class
Understanding Solutions
Understanding Main Ideas
The diagram below shows three mixtures. Identify each mixture as a solution, colloid, or
suspension. Explain.
1.
2.
3.
Answer the following questions on a separate sheet of paper.
4. Compare and contrast what happens to the particles of an ionic solid
and a molecular solid when each mixes with water.
5. What are two ways that solutes affect the properties of solvents?
Building Vocabulary
Fill in the blank to complete each statement.
6. The part of a solution that is present in the smaller amount is
the
.
7. The part of a solution that is present in larger amount is the
.
8. A(n)
is a mixture containing small, undissolved particles that
do not settle out, but are large enough to scatter light.
9. A mixture in which particles can be seen and easily separated by settling or filtration
is called a(n)
.
10. A well-mixed mixture that contains a solvent and at least one solute is called
a(n)
.
203D
Name
Date
Class
Understanding Solutions
Read the passage and study the flowchart below it. Then use a separate sheet of paper
to answer the questions that follow.
The Chemistry of Ice Cream
A colloid is similar to a suspension in that its particles are larger than those of a solution. However, the
particles of a colloid, like those of a solution, are small enough that they cannot be separated by settling
or filtration. The particles in a colloid are said to be dispersed, rather than dissolved or suspended.
Familiar colloids include shaving cream, fog, and smoke.
Ice cream is another familiar colloid. The particles in this colloid are solid fat, tiny crystals of ice, and
droplets of water. A high concentration of sugars, salts, and proteins is dissolved in the water. Here,
air acts something like a solvent. The particles of ice cream are dispersed in many tiny bubbles of air.
Ice cream also contains other substances that allow “unlike” compounds to mix and stay mixed under
the proper conditions. The unlike compounds in ice cream are water, which is polar, and fat, which is
nonpolar.
The colloid formed by ice cream remains stable only at cold temperatures. When ice cream is warmed
above freezing, its dispersed particles absorb energy and begin to move faster. When the fast-moving
particles collide, they sometimes stick together. Eventually, the particles grow so large that they can no
longer remain dispersed, and they settle out of the colloid.
Step 1
Solid and liquid
ingredients are combined.
Ingredients:
milk and cream,
sugar, flavoring,
water, fat, proteins,
substances to allow unlike
compounds to mix
Step 2
Mixture is churned and
cooled at the same time.
Churning adds air
and aids in rapid cooling.
1. Suppose the liquid water in ice cream did not have solutes dissolved
in it. What effect do you think this would have on ice cream?
(Hint: Consider the temperature at which ice cream is kept.)
2. What do you think happens to the air in the colloid when ice cream
melts?
3. Look at the diagram above. Why do you think air isn’t added until
Step 2 when the mixture is cooled?
4. Milk is also a colloid. It consists mainly of water, proteins, and fat.
Which colloid is more stable, milk or ice cream? How do you know?
203E
Step 3
Ice cream is cooled
further until it is
completely frozen.
Name
Date
Class
Understanding Solutions
Write the letter of the correct answer on the line at the left.
1.
Which of the statements about the
effect of solutes on solutions is true?
A Solutes raise the boiling point of a solvent.
B Water with a solute dissolved in it will
freeze at 0°C.
C Solutes raise the freezing point of a
solvent.
D Antifreeze boils at a lower temperature
than pure water.
2.
Brass is a solution in which a solid is
dissolved in a(n)
A liquid
B gas
C solid
D water
3.
Which of the following statements
about solutions is NOT true?
A Solutions are mixtures.
B Solutions contain a solvent dissolved in a
solute.
C A solution has the same properties
throughout.
D The solute in a solution can be a solid,
liquid, or gas.
4.
Which of the following statements
about the particles in a solution is true?
A When an ionic solid mixes with water, its
ions repel water molecules.
B When a molecular solid mixes with water,
the covalent bonds are broken.
C When an ionic solid mixes with water,
water molecules surround each ion.
D When a molecular solid mixes with water,
water molecules surround each ion.
If the statement is true, write true. If the statement is false, change the underlined word
or words to make the statement true.
5.
If a suspension is allowed to stand, the particles settle out.
6.
Solutions and colloids are similar in that both are suspensions.
The largest particles in a colloid are smaller than the largest
7.
particles in a solution.
8.
The freezing point of a solvent decreases as solute is added.
9.
Molecular compounds in water conduct an electric current.
10.
A characteristic property of a(n) solution is that it can scatter light.
203F
Name
Date
Class
Concentration and Solubility
How Is Concentration Changed?
1a. DESCRIBE What is a concentrated solution?
b. CALCULATE Find the concentration of a solution with 30 grams of
solute in 250 grams of solution.
c.
CHALLENGE
Solution A has twice as much solute as Solution B. Is it
possible for the solutions to have the same concentration? Explain.
I get it! Now I know that the concentration of a solution can be changed by
I need extra help with
What Factors Affect Solubility?
2a. REVIEW How can you tell when a solution is saturated?
b. CONTROL VARIABLES You are given two white powdery substances.
How would you use solubility to identify them?
c. ANSWER
What determines the properties of a solution?
I get it! Now I know that the solubility of a substance can be affected by
I need extra help with
211B
Name
Date
Class
Concentration and Solubility
On a separate sheet of paper, explain the difference between concentration and solubility.
Then describe how each can be changed.
211C
Name
Date
Class
Concentration and Solubility
Understanding Main Ideas
Answer the following questions in the spaces provided. Use a separate sheet of paper if
you need more room.
1. What amounts do you compare when measuring concentration?
2. How can you tell that a white powder is salt without tasting it?
3. Which solution will have more gas dissolved in it, a solution under
high pressure or one under low pressure?
4. How does temperature affect the solubility of most solids?
Building Vocabulary
Match each term with its definition by writing the letter of the correct definition in the
right column on the line beside the term in the left column.
5.
dilute solution
a. a measure of how much solute can dissolve in a
solvent at a given temperature
6.
concentrated solution
7.
solubility
b. a solution that has so much solute that no more can
dissolve
8.
saturated solution
c. a solution that has only a little solute
d. a solution that has a lot of solute
211D
Name
Date
Class
Concentration and Solubility
Study the two graphs. Then use a separate sheet of paper to answer the questions.
Temperature and Solubility
One of the factors that affects the solubility of a substance is temperature. The graphs below show how
the solubilities of different solids and gases change with the temperature of water.
1.
2.
3.
4.
5.
What are the manipulated variables and the responding variables on each graph?
What are the general trends in solubility implied by the two graphs?
Do all of the solids in the first graph follow the trend? Explain.
Which solid shows the greatest change in solubility with temperature?
At higher temperatures, gas particles move faster. Use this behavior
to explain the change in solubility of gases.
211E
Name
Date
Class
Concentration and Solubility
Fill in the blank to complete each statement.
1. A solution in which more solute can be dissolved is called a(n)
solution.
2. A solution in which 50 grams of solute is dissolved in 250 grams of solution has a
concentration of
percent.
3. When saturated solutions are
solutions.
, they usually become unsaturated
4. Ionic and polar compounds usually dissolve in
5. The concentration of a solution can be changed by
solvents.
solute.
If the statement is true, write true. If the statement is false, change the underlined word
or words to make the statement true.
6.
A solution in which only a little solute is dissolved in a certain
amount of solvent is called a(n) concentrated solution.
7.
As the pressure of the gas over a solution decreases, the
solubility of a gas solute in a liquid solvent increases.
The solubility of table sugar in water increases as the
8.
temperature increases.
9.
10.
The solubility of a gas dissolved in a liquid increases as the
temperature of the liquid increases.
Three factors that affect the solubility of a substance are
pressure, the type of solvent, and volume.
211F
Name
Date
Class
Describing Acids and Bases
What Are the Properties of Acids?
1a. DEFINE What is a compound that changes color in an acid called?
metal
indicator
carbonate
b. EXPLAIN Why are acids described as corrosive?
c. DRAW CONCLUSIONS How might you tell if a food contains an acid?
I get it! Now I know that the properties of acids include
I need extra help with
What Are the Properties of Bases?
2a. REVIEW The properties of bases are often considered (identical/
opposite) to acids.
b. APPLY CONCEPTS In what products are you most likely to find
bases in your home?
c. POSE QUESTIONS The color of hydrangea flowers depends on the amount of
acid or base in the soil. Write a question that helps you determine the
cause of a pink hydrangea.
I get it! Now I know that the properties of bases include
I need extra help with
217B
Name
Date
Class
Describing Acids and Bases
On a separate sheet of paper, describe how acids and bases are alike and how they are
different.
217C
Name
Date
Describing Acids and Bases
Understanding Main Ideas
Answer the following questions in the spaces provided.
1. When found in foods, what does an acid taste like?
2. When found in foods, what does a base taste like?
3. Compare how an acid and a base will each react with the metals
magnesium, zinc, and iron.
4. Compare how an acid and a base will each react with carbonate ions.
5. What color does an acid turn litmus paper?
6. What color does a base turn litmus paper?
7. What is neutralization?
Building Vocabulary
On a separate sheet of paper, write a definition for each of these terms.
8. corrosive
9. indicator
217D
Class
Name
Date
Class
Describing Acids and Bases
Read the passage and study the diagram below it. Then use a separate sheet of paper to
answer the questions that follow.
Acidic Paper
From the fifteenth through the eighteenth centuries, the paper in many books was made from linen.
Linen is made from the fibers of flax plants. By the nineteenth century, the printing of books had
increased dramatically and, as a result, so did the demand for inexpensive paper, In response, a method
was developed to produce cheap paper from wood. This process involved the use of a chemical called
alum, which greatly increased the acidity of paper. Eventually, this acidity causes such paper to become
brittle and fall apart. Thus, many books made during the nineteenth and twentieth centuries are slowly
becoming too fragile to read, while older books made with linen paper are often in better condition.
Scientists have developed several chemical methods to preserve books made with acidic paper. These
methods involve reacting the acid in the paper with a base. The products of these reactions are not
acidic, and so the paper is protected from further damage due to acidity. The diagram below illustrates
one of these processes. Today, some publishers use acid-free paper in their books. In fact, important
documents are sometimes printed on paper that is basic rather than acidic.
3. Air in the chamber is
replaced with nitrogen gas.
1. Books are
placed in a
special
chamber.
4. The gas diethyl zinc is
pumped into the chamber. The
gas moves between the pages
of the closed books and reacts
with acid in the paper.
2. Books
are dried,
removing
water.
1. Is paper made from linen more or less acidic than paper made from
wood? Which type of paper lasts longer?
2. The bases used to treat books containing acidic paper are usually
gases rather than liquid solutions. Why do you think this is so?
3. Why do you think that printing a document on basic paper will help
to ensure that it lasts for a very long time?
4. How might the process of making paper from wood be changed to
produce paper that is not acidic?
217E
Name
Date
Class
Describing Acids and Bases
Write the letter of the correct answer on the line at the left.
1.
Which of the following is NOT a
2.
Because it wears away certain
property of an acid?
materials, an acid is described as
A An acid is corrosive.
A concentrated
B An acid turns red litmus paper blue.
B contaminated
C An acid reacts with metals and carbonates.
C corrosive
D An acid tastes sour.
D carbonated
3.
Which of the following best describes
bases?
A They feel slippery and taste sour.
B They turn red litmus paper blue and react
with metals.
C They taste bitter and react with
carbonates.
D They turn red litmus paper blue and taste
bitter.
4.
Which of the following best describes
acids?
A They taste sour and react with metals.
B They taste bitter and react with
carbonates.
C They feel slippery and turn blue litmus
paper red.
D They react with metals but not with
carbonates.
Fill in the blank to complete each statement.
5. A compound that changes color when it comes into contact with an acid or a base
is a(n)
.
6. A base
react with carbonates.
7. If carbon dioxide gas is produced when dilute acid is applied to a rock’s surface,
the rock is most likely made of
.
8. Because vinegar contains a(n)
, it tastes sour.
9. Many soaps and detergents contain
.
10. The acid in the human stomach that aids in digestion is
217F
acid.
Name
Date
Class
Acids and Bases in Solution
What Ions Do Acids and Bases Form in Water?
1a. IDENTIFY What type of solution has a pH of 7?
acidic
basic
neutral
b. INTERPRET DATA Solution A has a pH of 1.6. Solution B has a pH of 4.
Which solution has a greater concentration of hydrogen ions? Explain.
I get it! Now I know that, in water, acids produce
and bases produce
.
I need extra help with
What Are the Products of Neutralization?
2a. DEFINE How is the scientific meaning of salt different
from the common meaning of salt?
b. MAKE GENERALIZATIONS Is the pH of an acid-base
neutralization always 7? Why or why not?
I get it! Now I know that a neutralization reaction produces
I need extra help with
223B
Name
Date
Class
Acids and Bases in Solution
On a separate sheet of paper, use the reaction between hydrochloric acid (HCl) and
potassium hydroxide (KOH) to describe a neutralization reaction in terms of reactants,
products, litmus paper, and pH.
223C
Name
Date
Class
Acids and Bases in Solution
Understanding Main Ideas
Complete the concept map shown below and answer the following questions on a
separate sheet of paper.
0 1
2 3
4
5
6 7 8
9 10 11 12 13 14
Substances with a pH
in this range are
1.
.
Substances with a pH
in this range are
2.
.
In water, they form
3.
In water, they form
4.
ions.
ions.
5. What is the difference between a strong acid and a weak acid?
6. What is the difference between a strong base and a weak base?
7. Which solution has a greater concentration of hydrogen ions (H+), a
solution with a pH of 3 or one with a pH of 7? Explain.
8. What are the products formed when a base reacts with an acid?
9. What is the pH of a neutral solution?
Building Vocabulary
Match each term with its definition by writing the letter of the correct definition in the
right column on the line beside the term in the left column.
10.
hydrogen ion
a. ionic compound that can form from the reaction of
an acid with a base
11.
pH scale
b. reaction between an acid and a base
12.
neutralization
c. H+
13.
salt
d. series of numbers that indicates the concentration of
hydrogen ions in solution
14.
hydroxide ion
e. OH–
223D
Name
Date
Class
Acids and Bases in Solution
Read the passage and study the graph below it. Then use a separate sheet of paper to
answer the questions that follow.
Swimming Pool Basics
If chemicals are not added to swimming pools, tiny organisms such as bacteria and algae can multiply in
the water. Algae can turn the water in a swimming pool cloudy and make the sides and bottom of the
pool slimy. Disease-causing bacteria can make swimmers sick. One chemical added to pools contains
−
hypochlorite ions (OCl ). A hypochlorite ion reacts with water to produce hypochlorous acid (HOCl) and a
hydroxide ion. Hypochlorous acid kills algae and bacteria. The equation for this reaction is:
−
OCl
+
Hypochlorite ion
H2O
Water
→
HOCl
Hypochlorous acid
+
−
OH
Hydroxide ion
The amount of hypochlorous acid that is produced by this reaction depends on the pH of the pool
water. The ideal pH for the above reaction is 7.4. Therefore, the pH of the pool water must be carefully
controlled. If the pH is too high (above 7.6), the reverse of the reaction above occurs! A hydroxide atom
reacts with hypochlorous acid to produce a hypochlorite ion and water. As a result, there will not be
enough hypochlorous acid in the pool water to control the bacteria and algae.
Problems also occur when the pH of the pool water is too low (less than 7.2). Pool water having a low
pH can damage the sides and bottom of the pool. Pool water having pH levels that are either too high
or too low can cause eye irritation in swimmers. The graph below shows how the relative amounts of
hypochlorous acid and hypochlorite ions vary with the pH of the pool water.
1. What happens to the amount of hypochlorous acid (HOCl) in a
swimming pool as the pH increases? What happens to the amount of
–
hypochlorite ions (OCl )?
2. What type of chemical could you add to a swimming pool to
decrease the pH of the water? Explain.
3. What type of chemical could you add to a swimming pool to increase
the pH of the water? Explain.
223E
Name
Date
Class
Acids and Bases in Solution
Write the letter of the correct answer on the line at the left.
1.
3.
Which of the following substances is
NOT an acid?
A HCl
B H2SO4
C NaOH
D HNO3
2.
Which of the following substances is
most likely to have a pH close to 7?
A lemon
B antacid
C ammonia
D vinegar
4.
The negative ion found in bases is
the
A hydroxide ion
B hydrogen ion
C carbonate ion
D water ion
Which of the following statements
is NOT true about neutralization?
A An acid and a base are the reactants.
B A salt and water are the products.
C There is no color change in litmus paper
when the reaction is over.
D It produces an acid-base mixture that
is more acidic than both the individual
starting solutions.
Fill in the blank to complete each statement.
5. A solution with a pH of 2 is
pH of 6.
acidic than a solution with a
6. Chemists use the
concentration of hydrogen ions in solution.
7. An acid produces
to express the
ions in water.
8. Substances with pH values close to 14 are strong
9. A strip of blue litmus paper placed in a beaker of vinegar will turn
.
10. A base produces
ions in water.
223F
.