Assignment Guide
SECTION
USING KEY TERMS
QUESTIONS
1
2, 7, 20
2
2–3, 8–11, 17–18, 20,
22–24
3
4–5, 13, 15, 24–27
4
1, 6, 12, 14, 16, 19, 21
1 In your own words, write a definition
for each of the following terms: meter,
temperature, and density.
For each pair of terms, explain how the
meanings of the terms differ.
9 A hypothesis
a. may or may not be testable.
b. is supported by evidence.
c. is a possible answer to a question.
d. All of the above
0 A variable
2 science and scientific methods
a. is found in an uncontrolled
ANSWERS
3 observation and hypothesis
b. is the factor that changes in an
Using Key Terms
4 theory and law
1. Sample answer: A meter is
a SI unit of length. Temperature
is the measure of how hot or
cold a substance is. Density is
a measure of how much mass
is in a given volume.
2. Sample answer: Science is
a process of observing and asking questions about the natural
world. Scientific methods are
the ways that scientists answer
questions and solve problems.
3. Sample answer: An observation is any use of the senses
to gather information. A hypothesis is a possible answer to a
question.
4. Sample answer: A theory
explains why something happens; a law only states what
happens.
5. Sample answer: A theory is
an explanation for how something happens. A model can represent an explanation or some
aspect of the theory.
5 model and theory
6 volume and mass
experiment.
c. cannot change.
d. is rarely included in experiments.
q Organizing data into a graph is an
example of
UNDERSTANDING KEY IDEAS
Multiple Choice
7 Physical science is
a. the study of matter and energy.
b. the study of physics and chemistry.
c. important in most sciences.
d. All of the above
8 The statement “Sheila has a stain on
her shirt” is an example of a(n)
a. law.
b. hypothesis.
c. observation.
d. prediction.
a. collecting data.
b. forming a hypothesis.
c. asking a question.
d. analyzing data.
w How many milliliters are in 3.5 kL?
a. 0.0035
c. 35,000
b. 3,500
d. 3,500,000
e A map of Seattle is an example of a
a. physical model.
b. mathematical model.
c. conceptual model.
d. All of the above
r Ten meters is equal to
a. 100 cm.
c. 100,000 mm.
b. 1,000 cm.
d. 1,000 µm.
Short Answer
t Describe three kinds of models used in
science. Give an example and explain
one limitation of each model.
6. Sample answer: Volume is the amount
of space taken up by an object, and mass is
the amount of matter an object contains.
Understanding Key Ideas
7. d
11. d
8. c
12. d
9. d
13. a
10. b
14. b
15. Sample answer: Physical models are representations or replicas of an object, such as
a model of a space shuttle or a globe. One
limitation of a physical model is that you
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experiment.
Chapter 1 • The World of Physical Science
cannot see how the actual object would
interact with its surroundings. Mathematical
models are made up of mathematical equations and data. An example would be a model
that forecasts weather. One limitation of
a mathematical model is that previously
unknown factors can cause the model to
fail. Conceptual models are models such
as systems of ideas, that make comparisons with familiar things. One limitation
of a conceptual model is that certain ideas
or data may not be taken into account
when the model is being formulated.
Critical Thinking
20.
y Name two SI units that can be used
d Evaluating Assumptions Suppose a
to describe the volume of an object
and two SI units that can be used to
describe the mass of an object.
classmate says, “I don’t need to study
science because I’m not going to be a
scientist, and scientists are the only
people who use science.” How would
you respond? In your answer, give
several examples of careers that use
physical science.
u What are the steps used in scientific
methods?
i If a hypothesis is not testable, is the
hypothesis wrong? Explain.
f Making Inferences You build a model
boat that you predict will float. However, your tests show that the boat
sinks. What conclusion would you
draw? Suggest some logical next steps.
Math Skills
o The cereal box
on the right has
a mass of 340 g.
Its dimensions are
27 cm 19 cm
6 cm. What is the
volume of the
box? What is its
density?
INTERPRETING GRAPHICS
Use the picture below to answer the
questions that follow.
CRITICAL THINKING
p Concept Mapping Use the following
terms to create a concept map: science,
scientific methods, hypothesis, problems,
questions, experiments, and observations.
a Applying Concepts A tailor is someone
who makes or alters items of clothing.
Why might a standard system of
measurement be helpful to a tailor?
s Analyzing Ideas Imagine that you are
conducting an experiment. You are
testing the effects of the height of a
ramp on the speed at which a toy car
goes down the ramp. What is the
variable in this experiment? What
factors must be controlled?
g How similar is this model to a real
object?
h What are some of the limitations of
this model?
j How might this model be useful?
16. Sample answer: Volume can be described
in mL or in g/cm3. Mass can be described in
g or kg.
17. asking a question, forming a hypothesis,
testing the hypothesis, analyzing the
results, drawing conclusions, and
communicating results
18. Sample answer: A hypothesis that is not
testable is not necessarily wrong, but it
cannot necessarily be supported either.
Unless a hypothesis can be tested, there
is no way to prove that it is wrong.
19. V ! 3,078 cm3 ; D ! 0.11 g/cm3
CHAPTER RESOURCES
Chapter Resource File
CRF
• Chapter Review g
• Chapter Test A g
• Chapter Test B s
• Chapter Test C a
• Vocabulary Activity g
Workbooks
Study Guide
• Assessment resources are
also available in Spanish.
An answer to this
exercise can be
found at the end
of this book.
21. Sample answer: A standard
system of measurement allows
a tailor to make clothing fit a
customer exactly.
22. Sample answer: The variable
is the height of the ramp. Some
of the factors that must be controlled are the equipment used,
the way the toy car is released,
the length of the track, and the
time measured.
23. Sample answer: Scientists are
not the only people who use
physical science. For example,
chefs have to understand how
food ingredients will interact, and
they have to measure quantities
properly, and firefighters must be
knowledgeable about the properties of different materials that
they might encounter in a fire.
24. Sample answer: I would conclude that the material I was
using was too dense or that
the shape that I was forming
the boat in was not displacing
enough water to allow the
boat to float. Some logical
next steps would be to find
another material or to change
the shape of the boat and then
perform the experiment again.
Interpreting Graphics
25. Sample answer: The model
is similar to the real object
in terms of structure and the
relative sizes of different
parts of the building. The
model also shows the location of the windows and
doors that will be built.
26. Sample answer: The model
does not show the interior features, such as plumbing, furniture, or carpeting. It also has
no electrical capabilities.
27. Sample answer: This model
shows what features this building would have without having
to be built full size.
Chapter 1 • Chapter Review
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