Question 1

Cholesterol is composed primarily of carbon and hydrogen atoms. Therefore, one would expect cholesterol to be

Accepted Answer

A)  insoluble in water. 
B)  a polar molecule. 
C)  a base. 
D)  an acid. 
E)  a buffer. 
A)  insoluble in water. 
B)  a polar molecule. 
C)  a base. 
D)  an acid. 
E)  a buffer.

Question 2

An atom that is neutrally charged contains

Accepted Answer

A)  only neutrons. 
B)  the same number of neutrons and electrons. 
C)  the same number of neutrons and protons. 
D)  the same number of protons and electrons. 
E)  no charged particles. 
A)  only neutrons. 
B)  the same number of neutrons and electrons. 
C)  the same number of neutrons and protons. 
D)  the same number of protons and electrons. 
E)  no charged particles.

Question 3

In a hydrogen molecule, the two atoms are held together by

Accepted Answer

A)  hydrogen bonds. 
B)  a shared pair of electrons. 
C)  van der Waals forces. 
D)  ionic attractions. 
E)  gravity. 
A)  hydrogen bonds. 
B)  a shared pair of electrons. 
C)  van der Waals forces. 
D)  ionic attractions. 
E)  gravity.

Question 4

An element that contains ten protons and ten electrons is likely to

Accepted Answer

A)  form covalent bonds with another element. 
B)  form ionic bonds with another element. 
C)  be chemically inert (stable). 
D)  be radioactive. 
E)  be toxic. 
A)  form covalent bonds with another element. 
B)  form ionic bonds with another element. 
C)  be chemically inert (stable). 
D)  be radioactive. 
E)  be toxic.

Question 5

Rank the elements carbon (C), hydrogen (H), oxygen (O), and phosphorus (P) in decreasing order of the number of covalent bonds they usually form.

Accepted Answer

A)  C > P > N > O > H 
B)  P > O > C > N > H 
C)  P > C > N > O > H 
D)  P > C > O > N > H 
E)  P > C > O > H > N 
A)  C > P > N > O > H 
B)  P > O > C > N > H 
C)  P > C > N > O > H 
D)  P > C > O > N > H 
E)  P > C > O > H > N

Question 6

Which component of an atom does not significantly add to its mass?

Accepted Answer

A)  Proton 
B)  Neutron 
C)  Electron 
D)  Both a and b 
E)  All of the above 
A)  Proton 
B)  Neutron 
C)  Electron 
D)  Both a and b 
E)  All of the above

Question 7

The strongest chemical bonds occur when

Accepted Answer

A)  two atoms share electrons in a covalent bond. 
B)  two atoms share electrons in an ionic bond. 
C)  hydrogen bonds are formed. 
D)  van der Waals forces are in effect. 
E)  there are hydrophobic interactions. 
A)  two atoms share electrons in a covalent bond. 
B)  two atoms share electrons in an ionic bond. 
C)  hydrogen bonds are formed. 
D)  van der Waals forces are in effect. 
E)  there are hydrophobic interactions.

Question 8

What is the difference between an element and a molecule?

Accepted Answer

A)  Molecules may be composed of different types of atoms, whereas elements are always composed of only one type of atom. 
B)  Molecules are composed of only one type of atom, whereas elements are composed of different types of atoms. 
C)  Molecules are elements. 
D)  Molecules always have larger atomic weights than elements. 
E)  Molecules do not have electrons, whereas elements do. 
A)  Molecules may be composed of different types of atoms, whereas elements are always composed of only one type of atom. 
B)  Molecules are composed of only one type of atom, whereas elements are composed of different types of atoms. 
C)  Molecules are elements. 
D)  Molecules always have larger atomic weights than elements. 
E)  Molecules do not have electrons, whereas elements do.

Question 9

Which of the following elements is contained by all living things?

Accepted Answer

A)  Nitrogen 
B)  Phosphorus 
C)  Sulfur 
D)  Carbon 
E)  All of the above 
A)  Nitrogen 
B)  Phosphorus 
C)  Sulfur 
D)  Carbon 
E)  All of the above

Question 10

The hydrogen bond between two water molecules arises because water is

Accepted Answer

A)  polar. 
B)  nonpolar. 
C)  a liquid. 
D)  small. 
E)  hydrophobic. 
A)  polar. 
B)  nonpolar. 
C)  a liquid. 
D)  small. 
E)  hydrophobic.

Question 11

If solution A has a pH of 2 and solution B has a pH of 8, which of the following statements is true?

Accepted Answer

A)  A is basic and B is acidic. 
B)  A is acidic and B is basic. 
C)  A is a base and B is an acid. 
D)  A has a greater [OH-] than B. 
E)  None of the above 
A)  A is basic and B is acidic. 
B)  A is acidic and B is basic. 
C)  A is a base and B is an acid. 
D)  A has a greater [OH-] than B. 
E)  None of the above

Question 12

Which of the following has the greatest concentration of hydrogen ions?

Accepted Answer

A)  Household ammonia at pH 11 
B)  Baking soda at pH 9 
C)  Human blood at pH 7 
D)  Black coffee at pH 5 
E)  Cola at pH 3 
A)  Household ammonia at pH 11 
B)  Baking soda at pH 9 
C)  Human blood at pH 7 
D)  Black coffee at pH 5 
E)  Cola at pH 3

Question 13

Given that Avagadro's number is 6.02 × 1023, how many molecules of KCl would there be in 10-13 liter of a 1 M KCl solution?

Accepted Answer

A)  6.02 × 1036 
B)  6.02 × 1010 
C)  6.02 × 10-10 
D)  6.02 × 103 
E)  6.02 × 1013 
A)  6.02 × 1036 
B)  6.02 × 1010 
C)  6.02 × 10-10 
D)  6.02 × 103 
E)  6.02 × 1013

Question 14

Oxygen forms _______ covalent bond(s), carbon forms _______, and hydrogen forms _______.

Accepted Answer

A)  one; four; one 
B)  four; four; four 
C)  two; four; none 
D)  two; four; one 
E)  two; two; two 
A)  one; four; one 
B)  four; four; four 
C)  two; four; none 
D)  two; four; one 
E)  two; two; two

Question 15

The best reference source for the atomic number and mass number of elements is

Accepted Answer

A)  a good chemistry text. 
B)  a dictionary. 
C)  the periodic table. 
D)  a general physics book. 
E)  a good biology text. 
A)  a good chemistry text. 
B)  a dictionary. 
C)  the periodic table. 
D)  a general physics book. 
E)  a good biology text.

Question 16

Ice floats because

Accepted Answer

A)  the crystal takes up more space than the liquid. 
B)  substances expand when cooled. 
C)  heat is released and heat makes water expand. 
D)  hydrogen bonds must break. 
E)  heat is absorbed. 
A)  the crystal takes up more space than the liquid. 
B)  substances expand when cooled. 
C)  heat is released and heat makes water expand. 
D)  hydrogen bonds must break. 
E)  heat is absorbed.

Question 17

The molecular weight of glucose (C6H12O6) is _______.

Accepted Answer

Question 18

The four elements most common in organisms are

Accepted Answer

A)  calcium, iron, hydrogen, and oxygen. 
B)  water, carbon, hydrogen, and oxygen. 
C)  carbon, oxygen, hydrogen, and nitrogen. 
D)  nitrogen, carbon, iron, and hydrogen. 
E)  phosphorus, water, carbon, and oxygen. 
A)  calcium, iron, hydrogen, and oxygen. 
B)  water, carbon, hydrogen, and oxygen. 
C)  carbon, oxygen, hydrogen, and nitrogen. 
D)  nitrogen, carbon, iron, and hydrogen. 
E)  phosphorus, water, carbon, and oxygen.

Question 19

3115P and 3215P have virtually identical chemical and biological properties because they have the same

Accepted Answer

A)  half-life. 
B)  number of neutrons. 
C)  atomic weight. 
D)  mass number. 
E)  number of electrons. 
A)  half-life. 
B)  number of neutrons. 
C)  atomic weight. 
D)  mass number. 
E)  number of electrons.

Question 20

Which of the following structures molecules is incorrect?

Accepted Answer

A)  CH3-NH3 
B)  CH2=CH2 
C)  CH3-NH2 
D)  CH3-NH3+ 
E)  CH3-CH3 
A)  CH3-NH3 
B)  CH2=CH2 
C)  CH3-NH2 
D)  CH3-NH3+ 
E)  CH3-CH3

Exam 2: Small Molecules and the Chemistry of Life

Cholesterol is composed primarily of carbon and hydrogen atoms. Therefore, one would expect cholesterol to be

An atom that is neutrally charged contains

In a hydrogen molecule, the two atoms are held together by

An element that contains ten protons and ten electrons is likely to

Rank the elements carbon (C), hydrogen (H), oxygen (O), and phosphorus (P) in decreasing order of the number of covalent bonds they usually form.

Which component of an atom does not significantly add to its mass?

The strongest chemical bonds occur when

What is the difference between an element and a molecule?

Which of the following elements is contained by all living things?

The hydrogen bond between two water molecules arises because water is

If solution A has a pH of 2 and solution B has a pH of 8, which of the following statements is true?

Which of the following has the greatest concentration of hydrogen ions?

Given that Avagadro's number is 6.02 × 1023, how many molecules of KCl would there be in 10-13 liter of a 1 M KCl solution?

Oxygen forms _______ covalent bond(s), carbon forms _______, and hydrogen forms _______.

The best reference source for the atomic number and mass number of elements is

Ice floats because

The molecular weight of glucose (C6H12O6) is _______.

The four elements most common in organisms are

3115P and 3215P have virtually identical chemical and biological properties because they have the same

Which of the following structures molecules is incorrect?

Studying Life

Proteins, Carbohydrates, and Lipids

Nucleic Acids and the Origin of Life

Cells: the Working Units of Life

Cell Membranes

Cell Signaling and Communication

Energy, Enzymes, and Metabolism

Pathways That Harvest Chemical Energy

Photosynthesis: Energy From Sunlight

The Cell Cycle and Cell Division

Inheritance, Genes, and Chromosomes

Dna and Its Role in Heredity

From Dna to Protein: Gene Expression

Gene Mutation and Molecular Medicine

Regulation of Gene Expression

Genomes

Recombinent Dna and Biotechnology

Differential Gene Expression in Development

Development and Evolutionary Change

Evidence and Mechanisms of Evolution

Reconstructing and Using Phylogenies

Species and Their Formation

Evolution of Genes and Genomes

The History of Life on Earth

Bacteria and Archaea: the Prokaryotic Domains

The Origin and Diversification of Eukaryotes

Plants Without Seeds: From Water to Land

The Evolution of Seed Plants

Fungi: Recyclers, Pathogens, Parasites, and Plant Partners

Animal Origins and the Evolution of Body Plans

Protostome Animals

Deuterostome Animals

The Plant Body

Transport in Plants

Plant Nutrition

Regulation of Plant Growth

Reproduction in Flowering Plants

Plant Responses to Environmental Challenges

Physiology, Homeostasis, and Temperature Regulation

Animal Hormones

Immunology: Animal Defense Systems

Animal Reproduction

Animal Development

Neurons and Nervous Systems

Sensory Systems

The Mammalian Nervous System: Structure and Higher Function

Musculoskeletal Systems

Gas Exchange in Animals

Circulatory Systems

Nutrition, Digestion, and Absorption

Salt and Water Balance and Nitrogen

Animal Behavior

Ecology and the Distribution of Life

Population Ecology

Species Interaction and Coevolution

Community Ecology

Ecosystems and Global Ecology

Conservation Biology

Filters

Given that Avagadro's number is 6.02 × 10²³, how many molecules of KCl would there be in 10^-¹³ liter of a 1 M KCl solution?

Oxygen forms ___ covalent bond(s), carbon forms _, and hydrogen forms _____.

The molecular weight of glucose (C₆H₁₂O₆) is _______.

³¹₁₅P and ³²₁₅P have virtually identical chemical and biological properties because they have the same