Question 1

Why is the pH of a 0.1 M solution of acetic acid in water higher than that of a 0.1 M solution of HCl in water?

Accepted Answer

A)  HCl is a weaker acid than acetic acid. 
B)  The acetic acid does not fully ionize in water, but HCl does. 
C)  HCl does not fully ionize in water, but acetic acid does. 
D)  Acetic acid is a better buffer than HCl. 
E)  Acetate (ionized acetic acid) is a strong base. 
A)  HCl is a weaker acid than acetic acid. 
B)  The acetic acid does not fully ionize in water, but HCl does. 
C)  HCl does not fully ionize in water, but acetic acid does. 
D)  Acetic acid is a better buffer than HCl. 
E)  Acetate (ionized acetic acid) is a strong base.

Question 2

Water is a polar molecule. This property contributes to cohesion and surface tension. Draw six water molecules. In your drawing, indicate how hydrogen bonding between molecules contributes to cohesion and surface tension. (Be sure to include appropriate covalent bonds in each molecule.)

Accepted Answer

Three pairs of electrons are shared betw

Question 3

Which of the following is the correct order (in decreasing order) for the relative strengths of chemical bonds?

Accepted Answer

A)  Covalent, ionic, hydrogen, van der Waals forces 
B)  Ionic, covalent, hydrogen, van der Waals forces 
C)  van der Waals forces, covalent, ionic, hydrogen 
D)  Hydrogen, covalent, van der Waals forces, ionic 
E)  Ionic, covalent, van der Waals forces, hydrogen 
A)  Covalent, ionic, hydrogen, van der Waals forces 
B)  Ionic, covalent, hydrogen, van der Waals forces 
C)  van der Waals forces, covalent, ionic, hydrogen 
D)  Hydrogen, covalent, van der Waals forces, ionic 
E)  Ionic, covalent, van der Waals forces, hydrogen

Question 4

Covalent bond formation depends on the ability of atoms to

Accepted Answer

A)  share electrons with other atoms. 
B)  donate electrons to other atoms. 
C)  receive electrons from other atoms. 
D)  Both a and b 
E)  All of the above 
A)  share electrons with other atoms. 
B)  donate electrons to other atoms. 
C)  receive electrons from other atoms. 
D)  Both a and b 
E)  All of the above

Question 5

A _______ is two or more atoms linked by chemical bonds.

Accepted Answer

The answer of A _______ is two or more atoms...

Question 6

The part of the atom that determines how the atom behaves chemically is the

Accepted Answer

A)  proton. 
B)  electron. 
C)  neutron. 
D)  innermost shell. 
E)  nucleus. 
A)  proton. 
B)  electron. 
C)  neutron. 
D)  innermost shell. 
E)  nucleus.

Question 7

Which of the following pairs has similar chemical properties?

Accepted Answer

A)  1H and 22Na 
B)  12C and 28Si 
C)  16O and 8S 
D)  12C and 14C 
E)  8H and 2He 
A)  1H and 22Na 
B)  12C and 28Si 
C)  16O and 8S 
D)  12C and 14C 
E)  8H and 2He

Question 8

The atomic number of an element

Accepted Answer

A)  equals the number of neutrons in an atom. 
B)  equals the number of protons in an atom. 
C)  equals the number of protons minus the number of neutrons. 
D)  equals the number of neutrons plus the number of protons. 
E)  depends on the isotope. 
A)  equals the number of neutrons in an atom. 
B)  equals the number of protons in an atom. 
C)  equals the number of protons minus the number of neutrons. 
D)  equals the number of neutrons plus the number of protons. 
E)  depends on the isotope.

Question 9

The compounds that sulfur forms with hydrogen are most like the compounds found in which of the following?

Accepted Answer

A)  CH4 
B)  NH3 
C)  H2O 
D)  NaCl 
E)  CaCl2 
A)  CH4 
B)  NH3 
C)  H2O 
D)  NaCl 
E)  CaCl2

Question 10

How would you make 100 ml of an aqueous solution with a 0.25 M concentration of a compound that has a molecular weight of 200 daltons?

Accepted Answer

A)  Add 0.25 grams of the compound to 100 ml of water. 
B)  Add 250 grams of the compound to 100 ml of water. 
C)  Take 250 grams of the compound and add water until the volume equals 100 ml. 
D)  Take 50 grams of the compound and add water until the volume equals 100 ml. 
E)  Take 5 grams of the compound and add water until the volume equals 100 ml. 
A)  Add 0.25 grams of the compound to 100 ml of water. 
B)  Add 250 grams of the compound to 100 ml of water. 
C)  Take 250 grams of the compound and add water until the volume equals 100 ml. 
D)  Take 50 grams of the compound and add water until the volume equals 100 ml. 
E)  Take 5 grams of the compound and add water until the volume equals 100 ml.

Question 11

An atom with _______ has an atomic mass of 14.

Accepted Answer

A)  14 neutrons 
B)  14 electrons 
C)  7 neutrons and 7 electrons 
D)  7 protons and 7 electrons 
E)  6 protons and 8 neutrons 
A)  14 neutrons 
B)  14 electrons 
C)  7 neutrons and 7 electrons 
D)  7 protons and 7 electrons 
E)  6 protons and 8 neutrons

Question 12

Why does ice float in water?

Accepted Answer

A)  Ice is less dense than water. 
B)  There are no hydrogen bonds in ice. 
C)  Ice is denser than water. 
D)  Water has a higher heat capacity than ice. 
E)  Ice has more covalent bonds than water. 
A)  Ice is less dense than water. 
B)  There are no hydrogen bonds in ice. 
C)  Ice is denser than water. 
D)  Water has a higher heat capacity than ice. 
E)  Ice has more covalent bonds than water.

Question 13

A 1.0 M solution of HCl has a pH of

Accepted Answer

A)  1.0. 
B)  7.0. 
C)  14.0. 
D)  11.2. 
E)  14. 
A)  1.0. 
B)  7.0. 
C)  14.0. 
D)  11.2. 
E)  14.

Question 14

Which contains more molecules, a mole of hydrogen or a mole of carbon?

Accepted Answer

A)  A mole of carbon 
B)  A mole of hydrogen 
C)  Both contain the same number of molecules. 
D)  Inadequate information is provided. 
E)  It depends on atmospheric pressure. 
A)  A mole of carbon 
B)  A mole of hydrogen 
C)  Both contain the same number of molecules. 
D)  Inadequate information is provided. 
E)  It depends on atmospheric pressure.

Question 15

One dalton is the same as the mass of one _______.

Accepted Answer

The answer of One dalton is the same as the...

Question 16

The molecular weight of glucose is 180. If you added 180 grams of glucose to a 0.5 liter of water, what would be the molarity of the resulting solution? (See Figure 2.2 for the periodic table.)

Accepted Answer

A)  18 
B)  1 
C)  9 
D)  2 
E)  0.5 
A)  18 
B)  1 
C)  9 
D)  2 
E)  0.5

Question 17

_______ occurs when one atom, such as 14C, is transformed into another atom, such as 14N, with an accompanying emission of energy.

Accepted Answer

Question 18

In addition to covalent and ionic bonds, which of the following interactions are important in biological systems?

Accepted Answer

A)  van der Waals interactions 
B)  Hydrogen bonds 
C)  Hydrophobic interactions 
D)  Both a and b 
E)  All of the above 
A)  van der Waals interactions 
B)  Hydrogen bonds 
C)  Hydrophobic interactions 
D)  Both a and b 
E)  All of the above

Question 19

The attraction between a slight positive charge on a hydrogen atom and the slight negative charge of a nearby electronegative atom is a _______.

Accepted Answer

The answer of The attraction between a slight positive charge...

Question 20

If you have 12 moles of a substance, how many molecules do you have of that substance? Suppose the substance has a molecular weight of 342. How many grams of that substance would you have to dissolve in a liter of water to make a 12 M solution?

Accepted Answer

You would multiply Avogadro's number (6.

Exam 2: Small Molecules and the Chemistry of Life

Why is the pH of a 0.1 M solution of acetic acid in water higher than that of a 0.1 M solution of HCl in water?

Water is a polar molecule. This property contributes to cohesion and surface tension. Draw six water molecules. In your drawing, indicate how hydrogen bonding between molecules contributes to cohesion and surface tension. (Be sure to include appropriate covalent bonds in each molecule.)

Which of the following is the correct order (in decreasing order) for the relative strengths of chemical bonds?

Covalent bond formation depends on the ability of atoms to

A _______ is two or more atoms linked by chemical bonds.

The part of the atom that determines how the atom behaves chemically is the

Which of the following pairs has similar chemical properties?

The atomic number of an element

The compounds that sulfur forms with hydrogen are most like the compounds found in which of the following?

How would you make 100 ml of an aqueous solution with a 0.25 M concentration of a compound that has a molecular weight of 200 daltons?

An atom with _______ has an atomic mass of 14.

Why does ice float in water?

A 1.0 M solution of HCl has a pH of

Which contains more molecules, a mole of hydrogen or a mole of carbon?

One dalton is the same as the mass of one _______.

The molecular weight of glucose is 180. If you added 180 grams of glucose to a 0.5 liter of water, what would be the molarity of the resulting solution? (See Figure 2.2 for the periodic table.)

_______ occurs when one atom, such as 14C, is transformed into another atom, such as 14N, with an accompanying emission of energy.

In addition to covalent and ionic bonds, which of the following interactions are important in biological systems?

The attraction between a slight positive charge on a hydrogen atom and the slight negative charge of a nearby electronegative atom is a _______.

If you have 12 moles of a substance, how many molecules do you have of that substance? Suppose the substance has a molecular weight of 342. How many grams of that substance would you have to dissolve in a liter of water to make a 12 M solution?

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

_______ occurs when one atom, such as ¹⁴C, is transformed into another atom, such as ¹⁴N, with an accompanying emission of energy.