Question 1

Which one of the atoms shown would be most likely to form an anion with a charge of -1?

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)    D

Question 2

The atomic number of sulfur is 16. Sulfur combines with hydrogen by covalent bonding to form a compound, hydrogen sulfide. Based on the number of valence electrons in a sulfur atom, predict the molecular formula of the compound:

Accepted Answer

A)  HS 
B)  HS₂ 
C)  H₂S 
D)  H₃S₂ 
E)  H₄S 
A)  HS 
B)  HS₂ 
C)  H₂S 
D)  H₃S₂ 
E)  H₄S C

Question 3

Which of the following is not considered to be a weak molecular interaction?

Accepted Answer

A)  a covalent bond 
B)  a van der Waals interaction 
C)  an ionic bond in the presence of water 
D)  a hydrogen bond 
E)  both a hydrogen bond and a covalent bond 
A)  a covalent bond 
B)  a van der Waals interaction 
C)  an ionic bond in the presence of water 
D)  a hydrogen bond 
E)  both a hydrogen bond and a covalent bond A

Question 4

How many electron pairs are shared between carbon atoms in a molecule that has the formula C₂H₄?

Accepted Answer

A)  0 
B)  1 
C)  2 
D)  3 
E)  4 
A)  0 
B)  1 
C)  2 
D)  3 
E)  4

Question 5

Which of the following pairs of atoms would be most likely to form a polar covalent bond?

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 6

About 25 of the 92 natural elements are known to be essential to life. Which four of these 25 elements make up approximately 96% of living matter?

Accepted Answer

A)  carbon, sodium, hydrogen, nitrogen 
B)  carbon, oxygen, phosphorus, hydrogen 
C)  oxygen, hydrogen, calcium, nitrogen 
D)  carbon, hydrogen, nitrogen, oxygen 
E)  carbon, oxygen, nitrogen, calcium 
A)  carbon, sodium, hydrogen, nitrogen 
B)  carbon, oxygen, phosphorus, hydrogen 
C)  oxygen, hydrogen, calcium, nitrogen 
D)  carbon, hydrogen, nitrogen, oxygen 
E)  carbon, oxygen, nitrogen, calcium

Question 7

One difference between carbon-12(   )is that carbon-14(   )has

Accepted Answer

A)  two more protons than carbon-12. 
B)  two more electrons than carbon-12. 
C)  two more neutrons than carbon-12. 
D)  two more protons and two more neutrons than carbon-12. 
E)  two more electrons and two more neutrons than carbon-12. 
A)  two more protons than carbon-12. 
B)  two more electrons than carbon-12. 
C)  two more neutrons than carbon-12. 
D)  two more protons and two more neutrons than carbon-12. 
E)  two more electrons and two more neutrons than carbon-12.

Question 8

What bonding or interaction is most likely to occur among a broad array of molecules of various types (polar, nonpolar, hydrophilic, hydrophobic)?

Accepted Answer

A)  covalent bonding 
B)  polar covalent bonding 
C)  ionic bonding 
D)  hydrogen bonding 
E)  van der Waals interactions 
A)  covalent bonding 
B)  polar covalent bonding 
C)  ionic bonding 
D)  hydrogen bonding 
E)  van der Waals interactions

Question 9

A covalent bond is likely to be polar when

Accepted Answer

A)  one of the atoms sharing electrons is much more electronegative than the other atom. 
B)  the two atoms sharing electrons are equally electronegative. 
C)  oxygen is one of the two atoms sharing electrons. 
D)  one of the atoms has absorbed more energy than the other atom. 
E)  the two atoms sharing electrons are different elements. 
A)  one of the atoms sharing electrons is much more electronegative than the other atom. 
B)  the two atoms sharing electrons are equally electronegative. 
C)  oxygen is one of the two atoms sharing electrons. 
D)  one of the atoms has absorbed more energy than the other atom. 
E)  the two atoms sharing electrons are different elements.

Question 10

Two atoms appear to have the same mass number. These atoms

Accepted Answer

A)  must have the same atomic number. 
B)  must have the same number of electrons. 
C)  must have the same chemical properties. 
D)  must have the same number of protons + neutrons. 
E)  must have the same atomic number, the same number of protons + neutrons, the same number of electrons, and the same chemical properties. 
A)  must have the same atomic number. 
B)  must have the same number of electrons. 
C)  must have the same chemical properties. 
D)  must have the same number of protons + neutrons. 
E)  must have the same atomic number, the same number of protons + neutrons, the same number of electrons, and the same chemical properties.

Question 11

-What results from the chemical reaction illustrated above?

Accepted Answer

A)  a cation with a net charge of +1 
B)  a cation with a net charge of -1 
C)  an anion with a net charge of +1 
D)  an anion with a net charge of -1 
E)  a cation with a net charge of +1 and an anion with a net charge of -1 
A)  a cation with a net charge of +1 
B)  a cation with a net charge of -1 
C)  an anion with a net charge of +1 
D)  an anion with a net charge of -1 
E)  a cation with a net charge of +1 and an anion with a net charge of -1

Question 12

If a salamander relied on hydrogen bonds to cling to surfaces, what type of surface would cause the most problems for this animal?

Accepted Answer

A)  a surface coated with a thin film of water 
B)  a surface made with carbon and hydrogen atoms covalently bonded together 
C)  a surface made with carbon, hydrogen, and oxygen atoms covalently bonded together 
D)  a surface made with carbon, hydrogen, nitrogen, and oxygen atoms covalently bonded together 
E)  a surface made with silicon and oxygen atoms covalently bonded together 
A)  a surface coated with a thin film of water 
B)  a surface made with carbon and hydrogen atoms covalently bonded together 
C)  a surface made with carbon, hydrogen, and oxygen atoms covalently bonded together 
D)  a surface made with carbon, hydrogen, nitrogen, and oxygen atoms covalently bonded together 
E)  a surface made with silicon and oxygen atoms covalently bonded together

Question 13

Which of the following best describes the relationship between the atoms described below?

Accepted Answer

A)  They are isomers. 
B)  They are polymers. 
C)  They are isotopes. 
D)  They contain 1 and 3 protons, respectively. 
E)  They each contain 1 neutron. 
A)  They are isomers. 
B)  They are polymers. 
C)  They are isotopes. 
D)  They contain 1 and 3 protons, respectively. 
E)  They each contain 1 neutron.

Question 14

The atomic number of nitrogen is 7. Nitrogen-15 is heavier than nitrogen-14 because the atomic nucleus of nitrogen-15 contains how many neutrons?

Accepted Answer

A)  6 
B)  7 
C)  8 
D)  12 
E)  14 
A)  6 
B)  7 
C)  8 
D)  12 
E)  14

Question 15

An atom has 6 electrons in its outer shell. How many unpaired electrons does it have?

Accepted Answer

A)  0 
B)  2 
C)  4 
D)  6 
E)  2 or 4 
A)  0 
B)  2 
C)  4 
D)  6 
E)  2 or 4

Question 16

In the term trace element, the modifier trace means that

Accepted Answer

A)  the element is required in very small amounts. 
B)  the element can be used as a label to trace atoms through an organism's metabolism. 
C)  the element is very rare on Earth. 
D)  the element enhances health but is not essential for the organism's long-term survival. 
E)  the element passes rapidly through the organism. 
A)  the element is required in very small amounts. 
B)  the element can be used as a label to trace atoms through an organism's metabolism. 
C)  the element is very rare on Earth. 
D)  the element enhances health but is not essential for the organism's long-term survival. 
E)  the element passes rapidly through the organism.

Question 17

In comparing covalent bonds and ionic bonds, which of the following would you expect?

Accepted Answer

A)  An atom can form covalent bonds with multiple partner atoms, but only a single ionic bond with a single partner atom. 
B)  Covalent bonds and ionic bonds occupy opposite ends of a continuous spectrum, from nearly equal to completely unequal sharing of electrons. 
C)  Both involve electrical attraction between the electrons of one atom and the nucleus of the other atom. 
D)  Ionic interactions remain when covalent bonds are broken in water. Ionic bonds are much stronger than covalent bonds. 
A)  An atom can form covalent bonds with multiple partner atoms, but only a single ionic bond with a single partner atom. 
B)  Covalent bonds and ionic bonds occupy opposite ends of a continuous spectrum, from nearly equal to completely unequal sharing of electrons. 
C)  Both involve electrical attraction between the electrons of one atom and the nucleus of the other atom. 
D)  Ionic interactions remain when covalent bonds are broken in water. Ionic bonds are much stronger than covalent bonds.

Question 18

Which of the following statements is false?

Accepted Answer

A)  Carbon, hydrogen, oxygen, and nitrogen are the most abundant elements of living matter. 
B)  Some trace elements are very abundant on Earth. 
C)  Virtually all organisms require the same elements in the same quantities. 
D)  Iron is an example of an element needed by all organisms. 
E)  Other than some trace elements, animals are mostly made up of the same elements as plants, in similar proportions. 
A)  Carbon, hydrogen, oxygen, and nitrogen are the most abundant elements of living matter. 
B)  Some trace elements are very abundant on Earth. 
C)  Virtually all organisms require the same elements in the same quantities. 
D)  Iron is an example of an element needed by all organisms. 
E)  Other than some trace elements, animals are mostly made up of the same elements as plants, in similar proportions.

Question 19

The atomic number of neon is 10. Therefore, which of the following is most correct about an atom of neon?

Accepted Answer

A)  It has 8 electrons in its outer electron shell. 
B)  It is inert. 
C)  It has an atomic mass of 10 daltons. 
D)  It has 8 electrons in its outer electron shell and it is inert. 
E)  It has 8 electrons in its outer electron shell, it is inert, and it has an atomic mass of 10 daltons. 
A)  It has 8 electrons in its outer electron shell. 
B)  It is inert. 
C)  It has an atomic mass of 10 daltons. 
D)  It has 8 electrons in its outer electron shell and it is inert. 
E)  It has 8 electrons in its outer electron shell, it is inert, and it has an atomic mass of 10 daltons.

Question 20

Electrons exist only at fixed levels of potential energy. However, if an atom absorbs sufficient energy, a possible result is that

Accepted Answer

A)  an electron may move to an electron shell farther away from the nucleus. 
B)  an electron may move to an electron shell closer to the nucleus. 
C)  the atom may become a radioactive isotope. 
D)  the atom would become a positively charged ion, or cation, and become a radioactive isotope. 
E)  the atom would become a negatively charged ion, or anion. 
A)  an electron may move to an electron shell farther away from the nucleus. 
B)  an electron may move to an electron shell closer to the nucleus. 
C)  the atom may become a radioactive isotope. 
D)  the atom would become a positively charged ion, or cation, and become a radioactive isotope. 
E)  the atom would become a negatively charged ion, or anion.

Exam 2: The Chemical Context of Life

Which one of the atoms shown would be most likely to form an anion with a charge of -1?

The atomic number of sulfur is 16. Sulfur combines with hydrogen by covalent bonding to form a compound, hydrogen sulfide. Based on the number of valence electrons in a sulfur atom, predict the molecular formula of the compound:

Which of the following is not considered to be a weak molecular interaction?

How many electron pairs are shared between carbon atoms in a molecule that has the formula C₂H₄?

Which of the following pairs of atoms would be most likely to form a polar covalent bond?

About 25 of the 92 natural elements are known to be essential to life. Which four of these 25 elements make up approximately 96% of living matter?

One difference between carbon-12( )is that carbon-14( )has

What bonding or interaction is most likely to occur among a broad array of molecules of various types (polar, nonpolar, hydrophilic, hydrophobic)?

A covalent bond is likely to be polar when

Two atoms appear to have the same mass number. These atoms

-What results from the chemical reaction illustrated above?

If a salamander relied on hydrogen bonds to cling to surfaces, what type of surface would cause the most problems for this animal?

Which of the following best describes the relationship between the atoms described below?

The atomic number of nitrogen is 7. Nitrogen-15 is heavier than nitrogen-14 because the atomic nucleus of nitrogen-15 contains how many neutrons?

An atom has 6 electrons in its outer shell. How many unpaired electrons does it have?

In the term trace element, the modifier trace means that

In comparing covalent bonds and ionic bonds, which of the following would you expect?

Which of the following statements is false?

The atomic number of neon is 10. Therefore, which of the following is most correct about an atom of neon?

Electrons exist only at fixed levels of potential energy. However, if an atom absorbs sufficient energy, a possible result is that

Introduction: Themes in the Study of Life

Water and Life

Carbon and the Molecular Diversity of Life

The Structure and Function of Large Biological Molecules

A Tour of the Cell

Membrane Structure and Function

An Introduction to Metabolism

Cellular Respiration and Fermentation

Photosynthesis

Cell Communication

The Cell Cycle

Meiosis and Sexual Life Cycles

Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

The Molecular Basis of Inheritance

From Gene to Protein

Regulation of Gene Expression

Viruses

Biotechnology

Genomes and Their Evolution

Descent with Modification: A Darwinian View of Life

The Evolution of Populations

The Origin of Species

The History of Life on Earth

Phylogeny and the Tree of Life

Bacteria and Archaea

Protists

Plant Diversity I: How Plants Colonized Land

Plant Diversity II: The Evolution of Seed Plants

Fungi

An Overview of Animal Diversity

An Introduction to Invertebrates

The Origin and Evolution of Vertebrates

Plant Structure, Growth, and Development

Resource Acquisition and Transport in Vascular Plants

Soil and Plant Nutrition

Angiosperm Reproduction and Biotechnology

Plant Responses to Internal and External Signals

Basic Principles of Animal Form and Function

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Osmoregulation and Excretion

Hormones and the Endocrine System

Animal Reproduction

Animal Development

Neurons, Synapses, and Signaling

Nervous Systems

Sensory and Motor Mechanisms

Animal Behavior

An Introduction to Ecology and the Biosphere

Population Ecology

Community Ecology

Ecosystems and Restoration Ecology

Conservation Biology and Global Change

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