Chapter 21: Biochemistry
CHAPTER 1
Chemistry: An Introduction
1. The specific answer will depend on student experiences. In general, students are
intimidated by chemistry because they perceive it to be highly mathematical,
requiring a great deal of memorization, and having a difficult technical vocabulary.
Many students taking chemistry as a foundation science cannot see its relevance to
their major.
2. The answer will depend on student examples.
3. There are obviously many such examples. Many new drugs and treatments have
recently become available thanks to research in biochemistry and cell biology. New
long-wearing, more comfortable contact lenses have been produced by research in
polymer and plastics chemistry. Special plastics and metals were prepared for the
production of compact discs to replace vinyl phonograph records. As for the “dark
side,” chemistry contributes increased global pollution if not conducted carefully.
4. Answer depends on student responses/examples.
5. This answer depends on your own experience.
6. This answer depends on your own experience, but consider the following examples:
oven cleaner (the label says it contains sodium hydroxide; it converts the burned-on
grease in the oven to a soapy material that washes away); drain cleaner (the label says
it contains sodium hydroxide; it dissolves the clog of hair in the drain); stomach
antacid (the label says it contains calcium carbonate; it makes me belch and makes
my stomach feel better); hydrogen peroxide (the label says it is a 3% solution of
hydrogen peroxide; when applied to a wound, it bubbles); depilatory cream (the label
says it contains sodium hydroxide; it removes unwanted hair from skin).
7. David and Susan first recognized the problem (unexplained medical problems). A
possible explanation was then proposed (the glaze on their china might be causing
lead poisoning). The explanation was tested by experiment (it was determined that the
china did contain lead). A full discussion of this scenario is given in the text.
8. The scientist must recognize the problem and state it clearly, propose possible
solutions or explanations, and then decide through experimentation which solution or
explanation is best.
9. A law tells what happens; a theory is our attempt to explain why it happens.
Examples of laws include the law of conservation of mass and the ideal gas law (for
gases). A theory includes Einstein’s theory of general relativity.
10. Answer depends on student response. A quantitative observation must include a
number. For example “There are two windows in this room” represents a quantitative
observation, but “The walls of this room are yellow” is a qualitative observation.
11. Flow charts will vary. Figure 1.1 in the textbook shows a nice example with various
parts of the scientific method. The first step in the scientific method is to state the
1
, Chapter 21: Biochemistry
problem and collect data (make observations). Observations may be qualitative or
quantitative. The next step is to formulate hypotheses. A hypothesis is a possible
explanation for the observation. The final step is to perform experiments. An
experiment is something we do to test the hypothesis. We gather new information that
allows us to decide whether the hypothesis is supported by the new information we
have learned from the experiment. Experiments always produce new observations,
and this brings us back to the beginning of the process again. To explain the behavior
of a given part of nature, we repeat these steps many times. Laws and theories come
out of applying the scientific method.
12. False. Theories can be refined and changed because they are interpretations. They
represent possible explanations of why nature behaves in a particular way. Theories
are refined by performing experiments and making new observations, not by proving
the existing observations as false (which is something that can be witnessed and
recorded).
13. Answer depends on student responses/examples.
14. Scientists are human, too. When a scientist formulates a hypothesis, he or she wants it
to be proven correct. In academic research, for example, scientists want to be able to
publish papers on their work to gain renown and acceptance from their colleagues. In
industrial situations, the financial success of the individual and of the company as a
whole may be at stake. Politically, scientists may be under pressure from the
government to "beat the other guy."
15. Chemistry is not just a set of facts that have to be memorized. To be successful in
chemistry, you have to be able to apply what you have learned to new situations, new
phenomena, and new experiments. Rather than just learning a list of facts or studying
someone else’s solution to a problem, your instructor hopes you will learn how to
solve problems yourself, so that you will be able to apply what you have learned in
future circumstances.
16. Chemistry is not merely a list of observations, definitions, and properties. Chemistry
is the study of very real interactions among different samples of matter, whether
within a living cell, or in a chemical factory. When we study chemistry, at least in
the beginning, we try to be as general and as nonspecific as possible, so that the basic
principles learned can be applied to many situations. In a beginning chemistry course,
we learn to interpret and solve a basic set of very simple problems in the hope that the
method of solving these simple problems can be extended to more complex real life
situations later on. The actual solution to a problem, at this point, is not as important
as learning how to recognize and interpret the problem, and how to propose
reasonable, experimentally testable hypotheses.
17. In real life situations, the problems and applications likely to be encountered are not
simple textbook examples. One must be able to observe an event, hypothesize a
cause, and then test this hypothesis. One must be able to carry what has been learned
in class forward to new, different situations.
A good student will: learn the background and fundamentals of the subject from 18.
their classes and textbook; will develop the ability to recognize and solve problems
and to extend what was learned in the classroom to “real” situations; will learn to
make careful observations; and will be able to communicate effectively. While some
academic subjects may emphasize use of one or more of these skills, Chemistry
makes extensive use of all of them.
2
, Chapter 21: Biochemistry
CHAPTER 2
Measurements and Calculations
1. measurement
2. “Scientific notation” means we have to put the decimal point after the first significant
figure, and then express the order of magnitude of the number as a power of ten. So
we want to put the decimal point after the first 2:
2,421 → 2.421 × 10to some power
To be able to move the decimal point three places to the left in going from 2,421 to
2.421, means I will need a power of 103 after the number, where the exponent 3
shows that I moved the decimal point 3 places to the left.
2,421 → 2.421 × 10to some power = 2.421 × 103
3. a. 9.651
b. 3.521
c. 9.3241
d. 1.002
4. a. 107
b. 10–1
c. 10–5
d. 1012
5. a. positive
b. positive
c. negative
d. negative
6. a. negative
b. zero
c. negative
d. positive
7. a. The decimal point must be moved one space to the right, so the exponent is
negative; 0.5012 = 5.012 × 10–1.
b. The decimal point must be moved six spaces to the left, so the exponent is
positive; 5,012,000 = 5.012 × 106.
c. The decimal point must be moved six spaces to the right, so the exponent is
negative; 0.000005012 = 5.012 × 10–6.
3
, Chapter 21: Biochemistry
d. The decimal point does not have to be moved, so the exponent is zero;
5.012 = 5.012 × 100.
e. The decimal point must be moved three spaces to the left, so the exponent is
positive; 5012 = 5.012 × 103.
f. The decimal point must be moved three spaces to the right, so the exponent is
negative;
0.005012 = 5.012 × 10–3.
8. a. The decimal point must be moved three spaces to the right: 2,789
b. The decimal point must be moved three spaces to the left: 0.002789
c. The decimal point must be moved seven spaces to the right: 93,000,000
d. The decimal point must be moved one space to the right: 42.89
e. The decimal point must be moved 4 spaces to the right: 99,990
f. The decimal point must be moved 5 spaces to the left: 0.00009999
9. a. six spaces to the right
b. five spaces to the left
c. one space to the right
d. The decimal point does not have to be moved.
e. 18 spaces to the right
f. 16 spaces to the left
10. a. three spaces to the left
b. one space to the left
c. five spaces to the right
d. one space to the left
e. two spaces to the right
f. two spaces to the left
11. To say that scientific notation is in standard form means that you have a number
between 1 and 10, followed by an exponential term.
a. The decimal point must be moved 4 spaces to the left, so the exponent will be
4:
9.782 × 104
b. 42.14 must first be converted to 4.214 × 101 and then the exponents
combined:
4.214 × 104
c. 0.08214 must first be converted to 8.214 × 10–2 and then the exponents
combined:
8.214 × 10–5
d. The decimal point must be moved four spaces to the right, so the exponent
will be –4:
3.914 × 10–4
4
CHAPTER 1
Chemistry: An Introduction
1. The specific answer will depend on student experiences. In general, students are
intimidated by chemistry because they perceive it to be highly mathematical,
requiring a great deal of memorization, and having a difficult technical vocabulary.
Many students taking chemistry as a foundation science cannot see its relevance to
their major.
2. The answer will depend on student examples.
3. There are obviously many such examples. Many new drugs and treatments have
recently become available thanks to research in biochemistry and cell biology. New
long-wearing, more comfortable contact lenses have been produced by research in
polymer and plastics chemistry. Special plastics and metals were prepared for the
production of compact discs to replace vinyl phonograph records. As for the “dark
side,” chemistry contributes increased global pollution if not conducted carefully.
4. Answer depends on student responses/examples.
5. This answer depends on your own experience.
6. This answer depends on your own experience, but consider the following examples:
oven cleaner (the label says it contains sodium hydroxide; it converts the burned-on
grease in the oven to a soapy material that washes away); drain cleaner (the label says
it contains sodium hydroxide; it dissolves the clog of hair in the drain); stomach
antacid (the label says it contains calcium carbonate; it makes me belch and makes
my stomach feel better); hydrogen peroxide (the label says it is a 3% solution of
hydrogen peroxide; when applied to a wound, it bubbles); depilatory cream (the label
says it contains sodium hydroxide; it removes unwanted hair from skin).
7. David and Susan first recognized the problem (unexplained medical problems). A
possible explanation was then proposed (the glaze on their china might be causing
lead poisoning). The explanation was tested by experiment (it was determined that the
china did contain lead). A full discussion of this scenario is given in the text.
8. The scientist must recognize the problem and state it clearly, propose possible
solutions or explanations, and then decide through experimentation which solution or
explanation is best.
9. A law tells what happens; a theory is our attempt to explain why it happens.
Examples of laws include the law of conservation of mass and the ideal gas law (for
gases). A theory includes Einstein’s theory of general relativity.
10. Answer depends on student response. A quantitative observation must include a
number. For example “There are two windows in this room” represents a quantitative
observation, but “The walls of this room are yellow” is a qualitative observation.
11. Flow charts will vary. Figure 1.1 in the textbook shows a nice example with various
parts of the scientific method. The first step in the scientific method is to state the
1
, Chapter 21: Biochemistry
problem and collect data (make observations). Observations may be qualitative or
quantitative. The next step is to formulate hypotheses. A hypothesis is a possible
explanation for the observation. The final step is to perform experiments. An
experiment is something we do to test the hypothesis. We gather new information that
allows us to decide whether the hypothesis is supported by the new information we
have learned from the experiment. Experiments always produce new observations,
and this brings us back to the beginning of the process again. To explain the behavior
of a given part of nature, we repeat these steps many times. Laws and theories come
out of applying the scientific method.
12. False. Theories can be refined and changed because they are interpretations. They
represent possible explanations of why nature behaves in a particular way. Theories
are refined by performing experiments and making new observations, not by proving
the existing observations as false (which is something that can be witnessed and
recorded).
13. Answer depends on student responses/examples.
14. Scientists are human, too. When a scientist formulates a hypothesis, he or she wants it
to be proven correct. In academic research, for example, scientists want to be able to
publish papers on their work to gain renown and acceptance from their colleagues. In
industrial situations, the financial success of the individual and of the company as a
whole may be at stake. Politically, scientists may be under pressure from the
government to "beat the other guy."
15. Chemistry is not just a set of facts that have to be memorized. To be successful in
chemistry, you have to be able to apply what you have learned to new situations, new
phenomena, and new experiments. Rather than just learning a list of facts or studying
someone else’s solution to a problem, your instructor hopes you will learn how to
solve problems yourself, so that you will be able to apply what you have learned in
future circumstances.
16. Chemistry is not merely a list of observations, definitions, and properties. Chemistry
is the study of very real interactions among different samples of matter, whether
within a living cell, or in a chemical factory. When we study chemistry, at least in
the beginning, we try to be as general and as nonspecific as possible, so that the basic
principles learned can be applied to many situations. In a beginning chemistry course,
we learn to interpret and solve a basic set of very simple problems in the hope that the
method of solving these simple problems can be extended to more complex real life
situations later on. The actual solution to a problem, at this point, is not as important
as learning how to recognize and interpret the problem, and how to propose
reasonable, experimentally testable hypotheses.
17. In real life situations, the problems and applications likely to be encountered are not
simple textbook examples. One must be able to observe an event, hypothesize a
cause, and then test this hypothesis. One must be able to carry what has been learned
in class forward to new, different situations.
A good student will: learn the background and fundamentals of the subject from 18.
their classes and textbook; will develop the ability to recognize and solve problems
and to extend what was learned in the classroom to “real” situations; will learn to
make careful observations; and will be able to communicate effectively. While some
academic subjects may emphasize use of one or more of these skills, Chemistry
makes extensive use of all of them.
2
, Chapter 21: Biochemistry
CHAPTER 2
Measurements and Calculations
1. measurement
2. “Scientific notation” means we have to put the decimal point after the first significant
figure, and then express the order of magnitude of the number as a power of ten. So
we want to put the decimal point after the first 2:
2,421 → 2.421 × 10to some power
To be able to move the decimal point three places to the left in going from 2,421 to
2.421, means I will need a power of 103 after the number, where the exponent 3
shows that I moved the decimal point 3 places to the left.
2,421 → 2.421 × 10to some power = 2.421 × 103
3. a. 9.651
b. 3.521
c. 9.3241
d. 1.002
4. a. 107
b. 10–1
c. 10–5
d. 1012
5. a. positive
b. positive
c. negative
d. negative
6. a. negative
b. zero
c. negative
d. positive
7. a. The decimal point must be moved one space to the right, so the exponent is
negative; 0.5012 = 5.012 × 10–1.
b. The decimal point must be moved six spaces to the left, so the exponent is
positive; 5,012,000 = 5.012 × 106.
c. The decimal point must be moved six spaces to the right, so the exponent is
negative; 0.000005012 = 5.012 × 10–6.
3
, Chapter 21: Biochemistry
d. The decimal point does not have to be moved, so the exponent is zero;
5.012 = 5.012 × 100.
e. The decimal point must be moved three spaces to the left, so the exponent is
positive; 5012 = 5.012 × 103.
f. The decimal point must be moved three spaces to the right, so the exponent is
negative;
0.005012 = 5.012 × 10–3.
8. a. The decimal point must be moved three spaces to the right: 2,789
b. The decimal point must be moved three spaces to the left: 0.002789
c. The decimal point must be moved seven spaces to the right: 93,000,000
d. The decimal point must be moved one space to the right: 42.89
e. The decimal point must be moved 4 spaces to the right: 99,990
f. The decimal point must be moved 5 spaces to the left: 0.00009999
9. a. six spaces to the right
b. five spaces to the left
c. one space to the right
d. The decimal point does not have to be moved.
e. 18 spaces to the right
f. 16 spaces to the left
10. a. three spaces to the left
b. one space to the left
c. five spaces to the right
d. one space to the left
e. two spaces to the right
f. two spaces to the left
11. To say that scientific notation is in standard form means that you have a number
between 1 and 10, followed by an exponential term.
a. The decimal point must be moved 4 spaces to the left, so the exponent will be
4:
9.782 × 104
b. 42.14 must first be converted to 4.214 × 101 and then the exponents
combined:
4.214 × 104
c. 0.08214 must first be converted to 8.214 × 10–2 and then the exponents
combined:
8.214 × 10–5
d. The decimal point must be moved four spaces to the right, so the exponent
will be –4:
3.914 × 10–4
4
