Question 1

Which atom usually has the greatest number of covalent bonds with other atoms?

Accepted Answer

A)  Carbon 
B)  Oxygen 
C)  Sulfur 
D)  Hydrogen 
E)  Nitrogen 
A)  Carbon 
B)  Oxygen 
C)  Sulfur 
D)  Hydrogen 
E)  Nitrogen A

Question 2

Which observation makes a strong case that the study of water and its properties is relevant to the study of structural biology?

Accepted Answer

A)  Corals are marine animals that live in close association with photosynthetic algae that supply the corals with a source of food. 
B)  Some Arctic fish produce antifreeze proteins to prevent ice crystals from forming in their cells. 
C)  Animals that live in caves their entire lives rely on nutrients brought into their habitats by running water or by other organisms. 
D)  Ice loses mass as water molecules go from the solid state directly to the gas state. 
E)  Lake ecosystems can be destroyed by chemical fertilizers carried from farmland into lakes in rain runoff. 
A)  Corals are marine animals that live in close association with photosynthetic algae that supply the corals with a source of food. 
B)  Some Arctic fish produce antifreeze proteins to prevent ice crystals from forming in their cells. 
C)  Animals that live in caves their entire lives rely on nutrients brought into their habitats by running water or by other organisms. 
D)  Ice loses mass as water molecules go from the solid state directly to the gas state. 
E)  Lake ecosystems can be destroyed by chemical fertilizers carried from farmland into lakes in rain runoff. B

Question 3

Consider the following statement: Most biochemical reactions take place in aqueous solutions.This statement is

Accepted Answer

A)  true, because water is the solvent in an aqueous solution, and cells are full of water. 
B)  true, because water is the reactant in the aqueous solution. 
C)  false, because water is the reactant and cannot also be the aqueous solution. 
D)  false, because most biochemical reactions love water. 
E)  false, because most biochemical reactions involve enzymes and not water. 
A)  true, because water is the solvent in an aqueous solution, and cells are full of water. 
B)  true, because water is the reactant in the aqueous solution. 
C)  false, because water is the reactant and cannot also be the aqueous solution. 
D)  false, because most biochemical reactions love water. 
E)  false, because most biochemical reactions involve enzymes and not water. A

Question 4

Which property of water contributes most to the ability of fish in lakes to survive very cold winters?

Accepted Answer

A)  Strong cohesive forces 
B)  High heat capacity 
C)  Density differences at different temperatures 
D)  High surface tension 
E)  High heat of vaporization 
A)  Strong cohesive forces 
B)  High heat capacity 
C)  Density differences at different temperatures 
D)  High surface tension 
E)  High heat of vaporization

Question 5

Refer to the figure below.   Which diagrams show atoms that will lose electrons to form a stable ion? List all that apply.

Accepted Answer

The answer of Refer to the figure below.  ...

Question 6

Hydrocarbons are _______ and _______, whereas salts are _______ and _______.

Accepted Answer

A)  nonpolar; hydrophobic; polar; hydrophilic 
B)  nonpolar; hydrophilic; polar; hydrophobic 
C)  nonpolar; hydrophobic, nonpolar, hydrophilic 
D)  polar; hydrophilic; nonpolar; hydrophobic 
E)  polar; hydrophobic; nonpolar; hydrophilic 
A)  nonpolar; hydrophobic; polar; hydrophilic 
B)  nonpolar; hydrophilic; polar; hydrophobic 
C)  nonpolar; hydrophobic, nonpolar, hydrophilic 
D)  polar; hydrophilic; nonpolar; hydrophobic 
E)  polar; hydrophobic; nonpolar; hydrophilic

Question 7

Which statement about chemical reactions is false?

Accepted Answer

A)  They occur when atoms combine or change their bonding partners. 
B)  They may lead to the creation or destruction of energy. 
C)  They may go to completion. 
D)  They may lead to changes in forms of energy. 
E)  They convert reactants into products. 
A)  They occur when atoms combine or change their bonding partners. 
B)  They may lead to the creation or destruction of energy. 
C)  They may go to completion. 
D)  They may lead to changes in forms of energy. 
E)  They convert reactants into products.

Question 8

Some reactions, such as the decomposition of nitroglycerin in dynamite, release large amounts of energy in the form of heat.Others, such as those taking place inside cells, release much smaller amounts of heat.Which statement is true about these reactions?

Accepted Answer

A)  The total amount of energy involved in the cellular reactions is conserved, but new energy is created during the explosive reaction involving nitroglycerin. 
B)  Though a larger overall change in energy occurs in the nitroglycerin reaction, the total amount of energy present before and after each reaction does not change. 
C)  Cells use up energy, causing an overall decrease in the total amount of energy present before cellular reactions, while nonliving things, such as dynamite, do not. 
D)  Both living cells and nonliving things, such as dynamite, cause an overall loss of energy when they release heat during reactions. 
E)  Only living things conserve energy from their reactions in the form of chemical bond energy, while nonliving things, such as dynamite, lose energy when they react. 
A)  The total amount of energy involved in the cellular reactions is conserved, but new energy is created during the explosive reaction involving nitroglycerin. 
B)  Though a larger overall change in energy occurs in the nitroglycerin reaction, the total amount of energy present before and after each reaction does not change. 
C)  Cells use up energy, causing an overall decrease in the total amount of energy present before cellular reactions, while nonliving things, such as dynamite, do not. 
D)  Both living cells and nonliving things, such as dynamite, cause an overall loss of energy when they release heat during reactions. 
E)  Only living things conserve energy from their reactions in the form of chemical bond energy, while nonliving things, such as dynamite, lose energy when they react.

Question 9

The electronegativity of an atom is a relative measure of the

Accepted Answer

A)  number of electrons in an atom. 
B)  number of electrons in the atom's outermost electron shell. 
C)  difference between the number of atoms and the number of protons. 
D)  affinity an atom has for electrons and its ability to capture additional electrons. 
E)  affinity an atom has for protons and its ability to capture additional protons. 
A)  number of electrons in an atom. 
B)  number of electrons in the atom's outermost electron shell. 
C)  difference between the number of atoms and the number of protons. 
D)  affinity an atom has for electrons and its ability to capture additional electrons. 
E)  affinity an atom has for protons and its ability to capture additional protons.

Question 10

The mass of a proton serves as the standard unit of measure for 1 Da.A _______ also has a mass of about 1 Da.

Accepted Answer

The answer of The mass of a proton serves as...

Question 11

Refer to the figures below.   Which compound would have a higher heat of vaporization than water, and why?

Accepted Answer

A)  Compound A because it is smaller in size than water. 
B)  Compound A because unlike water, it is not capable of hydrogen bonding. 
C)  Compound B because it can form more hydrogen bonds per molecule than water. 
D)  Compound B because it contains more covalent bonds per molecule than water. 
E)  Compound C because it contains more oxygen atoms per molecule than water. 
A)  Compound A because it is smaller in size than water. 
B)  Compound A because unlike water, it is not capable of hydrogen bonding. 
C)  Compound B because it can form more hydrogen bonds per molecule than water. 
D)  Compound B because it contains more covalent bonds per molecule than water. 
E)  Compound C because it contains more oxygen atoms per molecule than water.

Question 12

Refer to the table below.   The table shows a summary of information about atomic particles under study in a physics lab.What could explain why two of the particles were affected by the electrical field while one particle remained unaffected?

Accepted Answer

A)  An imbalance in protons and electrons causes the effect. 
B)  Only particle 2 has an equal number of protons and neutrons. 
C)  Small particles are less influenced by electrical fields than large particles. 
D)  Having an odd number of protons causes a particle to be influenced by an electrical field. 
E)  Particle 2 has the fewest charged particles in its nucleus. 
A)  An imbalance in protons and electrons causes the effect. 
B)  Only particle 2 has an equal number of protons and neutrons. 
C)  Small particles are less influenced by electrical fields than large particles. 
D)  Having an odd number of protons causes a particle to be influenced by an electrical field. 
E)  Particle 2 has the fewest charged particles in its nucleus.

Question 13

Of the statements below, which best explains why the study of water is relevant to the study of living organisms?

Accepted Answer

A)  Water is produced when amino acids polymerize to form proteins and when nucleotides polymerize to form RNA and DNA. 
B)  Ninety-six percent of water on Earth is found in the oceans, 1 percent is found in bays and estuaries, and 3 percent is found in freshwater locations. 
C)  An average rainstorm drops about 100,000 liters of water over 1 acre of land. 
D)  Sixty percent of an adult human's body weight is due to water, with two-thirds of this water located inside cells and one-third outside cells. 
E)  Water is the only compound on Earth that can be found as a gas, a liquid, and a solid in different natural settings. 
A)  Water is produced when amino acids polymerize to form proteins and when nucleotides polymerize to form RNA and DNA. 
B)  Ninety-six percent of water on Earth is found in the oceans, 1 percent is found in bays and estuaries, and 3 percent is found in freshwater locations. 
C)  An average rainstorm drops about 100,000 liters of water over 1 acre of land. 
D)  Sixty percent of an adult human's body weight is due to water, with two-thirds of this water located inside cells and one-third outside cells. 
E)  Water is the only compound on Earth that can be found as a gas, a liquid, and a solid in different natural settings.

Question 14

Which pair has similar chemical properties?

Accepted Answer

A)  12C and 14C 
B)  12C and 40Ca 
C)  16O and 16N 
D)  1H and 22Na 
E)  18O and 45Ca 
A)  12C and 14C 
B)  12C and 40Ca 
C)  16O and 16N 
D)  1H and 22Na 
E)  18O and 45Ca

Question 15

To determine the number of molecules in a teaspoon of sugar, you have to know

Accepted Answer

A)  the mass of the sugar. 
B)  the mass and density of the sugar. 
C)  the molecular weight of the sugar. 
D)  Avogadro's number. 
E)  the mass and molecular weight of the sugar, and Avogadro's number. 
A)  the mass of the sugar. 
B)  the mass and density of the sugar. 
C)  the molecular weight of the sugar. 
D)  Avogadro's number. 
E)  the mass and molecular weight of the sugar, and Avogadro's number.

Question 16

The number of protons in a neutral atom equals the number of

Accepted Answer

A)  electrons. 
B)  neutrons. 
C)  electrons plus neutrons. 
D)  neutrons minus electrons. 
E)  isotopes. 
A)  electrons. 
B)  neutrons. 
C)  electrons plus neutrons. 
D)  neutrons minus electrons. 
E)  isotopes.

Question 17

Vertebrate animals rely on movement of sodium ions in and out of nerve cells to transmit nerve impulses.Which property of water is relevant to this function, and why?

Accepted Answer

A)  Water's strong adhesive properties, because this property explains the attraction between water and other substances 
B)  Water's changing density with temperature, because this property allows water to move as it heats up 
C)  Water's polarity, because this property makes it an effective solvent for charged particles 
D)  Water's high surface tension, because this property allows water to act as a surface that cannot be penetrated easily 
E)  Water's strong cohesive properties, because this property explains the attraction between water and itself 
A)  Water's strong adhesive properties, because this property explains the attraction between water and other substances 
B)  Water's changing density with temperature, because this property allows water to move as it heats up 
C)  Water's polarity, because this property makes it an effective solvent for charged particles 
D)  Water's high surface tension, because this property allows water to act as a surface that cannot be penetrated easily 
E)  Water's strong cohesive properties, because this property explains the attraction between water and itself

Question 18

An aqueous solution with a mixture of a _______ acid and its corresponding _______ is called a(n) _______.

Accepted Answer

A)  strong; base; molar solution 
B)  weak; base; buffer 
C)  strong; acid; ionic solution 
D)  strong; acid; buffer 
E)  weak; base; acid 
A)  strong; base; molar solution 
B)  weak; base; buffer 
C)  strong; acid; ionic solution 
D)  strong; acid; buffer 
E)  weak; base; acid

Question 19

A solution with pH 9 contains

Accepted Answer

A)  more H+ ions than OH- ions. 
B)  more OH- ions than H+ ions. 
C)  the same number of OH- ions and H+ ions. 
D)  no OH- ions. 
E)  only H- ions. 
A)  more H+ ions than OH- ions. 
B)  more OH- ions than H+ ions. 
C)  the same number of OH- ions and H+ ions. 
D)  no OH- ions. 
E)  only H- ions.

Question 20

Which set of numbers correctly balances the chemical equation below, describing the combustion of hexane?
 2 CXHY + 19 O2 F1F1F1S1F1F1F10 Z CO2 + 14 H2O + energy

Accepted Answer

A)  X = 6, Y = 12, Z = 10 
B)  X = 6, Y = 14, Z = 10 
C)  X = 6, Y = 14, Z = 12 
D)  X = 6, Y = 14, Z = 14 
E)  X = 6, Y = 16, Z = 12 
A)  X = 6, Y = 12, Z = 10 
B)  X = 6, Y = 14, Z = 10 
C)  X = 6, Y = 14, Z = 12 
D)  X = 6, Y = 14, Z = 14 
E)  X = 6, Y = 16, Z = 12

Exam 2: Small Molecules and the Chemistry of Life

Which atom usually has the greatest number of covalent bonds with other atoms?

Which observation makes a strong case that the study of water and its properties is relevant to the study of structural biology?

Consider the following statement: Most biochemical reactions take place in aqueous solutions.This statement is

Which property of water contributes most to the ability of fish in lakes to survive very cold winters?

Refer to the figure below. Which diagrams show atoms that will lose electrons to form a stable ion? List all that apply.

Hydrocarbons are _______ and _______, whereas salts are _______ and _______.

Which statement about chemical reactions is false?

Some reactions, such as the decomposition of nitroglycerin in dynamite, release large amounts of energy in the form of heat.Others, such as those taking place inside cells, release much smaller amounts of heat.Which statement is true about these reactions?

The electronegativity of an atom is a relative measure of the

The mass of a proton serves as the standard unit of measure for 1 Da.A _______ also has a mass of about 1 Da.

Refer to the figures below. Which compound would have a higher heat of vaporization than water, and why?

Refer to the table below. The table shows a summary of information about atomic particles under study in a physics lab.What could explain why two of the particles were affected by the electrical field while one particle remained unaffected?

Of the statements below, which best explains why the study of water is relevant to the study of living organisms?

Which pair has similar chemical properties?

To determine the number of molecules in a teaspoon of sugar, you have to know

The number of protons in a neutral atom equals the number of

Vertebrate animals rely on movement of sodium ions in and out of nerve cells to transmit nerve impulses.Which property of water is relevant to this function, and why?

An aqueous solution with a mixture of a _______ acid and its corresponding _______ is called a(n) _______.

A solution with pH 9 contains

Which set of numbers correctly balances the chemical equation below, describing the combustion of hexane? 2 CXHY + 19 O2  Z CO2 + 14 H2O + energy

Studying Life

Proteins, Carbohydrates, and Lipids

Nucleic Acids and the Origin of Life

Cells: the Working Units of Life

Cell Membranes

Cell Communication and Multicellularity

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

Recombinant Dna and Biotechnology

Mechanisms of Evolution

Reconstructing and Using Phylogenies

Speciation

Evolution of Genes and Genomes

The History of Life on Earth

Bacteria, Archaea, and Viruses

The Origin and Diversification of Eukaryotes

Plants Without Seeds: From Water to Land

The Evolution of Seed Plants

The Evolution and Diversity of Fungi

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, Glia, and Nervous Systems

Sensory Systems

The Mammalian Nervous System: Structure and Higher Functions

Musculoskeletal Systems

Gas Exchange

Circulatory Systems

Nutrition, Digestion, and Absorption

Salt and Water Balance and Nitrogen Excretion

Animal Behavior

The Physical Environment and Biogeography of Life

Populations

Species Interactions

Communities

Ecosystems

A Changing Biosphere

Filters

Hydrocarbons are ___ and _, whereas salts are _ and ___.

An aqueous solution with a mixture of a ___ acid and its corresponding _ is called a(n) _____.

Which set of numbers correctly balances the chemical equation below, describing the combustion of hexane? 2 C_XH_Y + 19 O₂  Z CO₂ + 14 H₂O + energy