Question 1

Two carbon atoms held together in a double covalent bond share _______ electron(s).

Accepted Answer

A)  one 
B)  two 
C)  four 
D)  six 
E)  eight 
A)  one 
B)  two 
C)  four 
D)  six 
E)  eight

Question 2

The subatomic particles that make up the majority of the mass of an atom are protons and _______.

Accepted Answer

The answer of The subatomic particles that make up the...

Question 3

Refer to the balanced chemical equation below. CH4 + 2 O2 F1F1F1S1F1F1F10F1F1F1S1F1F1F10 CO2 + 2 H2O + 890 kJ
Which graph represents the energy changes accompanying this reaction?

Accepted Answer

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

Question 4

Refer to the figure below showing the chemical structures of several molecules.   Which pair of molecules is most likely to be miscible (each soluble in the other)?

Accepted Answer

A)  Octane and water 
B)  Water and methanol 
C)  Amino acid and octane 
D)  Methanol and octane 
E)  Amino acid and methanol 
A)  Octane and water 
B)  Water and methanol 
C)  Amino acid and octane 
D)  Methanol and octane 
E)  Amino acid and methanol

Question 5

The equation C4H10 + 7 O2 F1F1F1S1F1F1F10 4 CO2 + 6 H2O + energy is incorrect because

Accepted Answer

A)  two carbon atoms are missing from the products. 
B)  two hydrogen atoms are missing from the products. 
C)  two carbon atoms are missing from the reactants. 
D)  two hydrogen atoms are missing from the reactants. 
E)  two oxygen atoms are missing from the products. 
A)  two carbon atoms are missing from the products. 
B)  two hydrogen atoms are missing from the products. 
C)  two carbon atoms are missing from the reactants. 
D)  two hydrogen atoms are missing from the reactants. 
E)  two oxygen atoms are missing from the products.

Question 6

Differences in the electronegativity of atoms that share electrons in a bond are involved in

Accepted Answer

A)  a polar covalent bond. 
B)  an ionic bond. 
C)  a hydrogen bond. 
D)  van der Waals forces. 
E)  hydrophobic interactions. 
A)  a polar covalent bond. 
B)  an ionic bond. 
C)  a hydrogen bond. 
D)  van der Waals forces. 
E)  hydrophobic interactions.

Question 7

Carbon-14 is a radioactive isotope of carbon.When an organism is alive, the total amount of carbon-14 in the organism's body remains constant.As soon as the organism dies, the amount of carbon-14 begins to decrease in a predictable way.This provides evidence for which statement about living organisms?

Accepted Answer

A)  Different organisms have different life-spans. 
B)  Living organisms are dynamic and constantly exchanging matter with the environment. 
C)  There is a huge diversity of life-forms represented among the organisms living today. 
D)  All living organisms are composed of cells. 
E)  Living organisms pass on biological information to their offspring. 
A)  Different organisms have different life-spans. 
B)  Living organisms are dynamic and constantly exchanging matter with the environment. 
C)  There is a huge diversity of life-forms represented among the organisms living today. 
D)  All living organisms are composed of cells. 
E)  Living organisms pass on biological information to their offspring.

Question 8

Oxygen and carbon are defined as different elements because they have atoms with different numbers of _______ in the nucleus.

Accepted Answer

The answer of Oxygen and carbon are defined as different...

Question 9

The two covalent bonds in a water molecule are polar because

Accepted Answer

A)  oxygen is more electronegative than hydrogen. 
B)  oxygen and hydrogen have similar electronegativities. 
C)  oxygen is less electronegative than hydrogen. 
D)  water is a small molecule. 
E)  water is hydrophilic. 
A)  oxygen is more electronegative than hydrogen. 
B)  oxygen and hydrogen have similar electronegativities. 
C)  oxygen is less electronegative than hydrogen. 
D)  water is a small molecule. 
E)  water is hydrophilic.

Question 10

Which equation represents a chemical reaction that obeys the law of conservation of matter?

Accepted Answer

A)  C6H12O6 + O2 F1F1F1S1F1F1F10 CO2 + H2O 
B)  C6H12O6 + 8 O2 F1F1F1S1F1F1F10 6 CO2 + 8 H2O 
C)  C6H12O6 + 12 O2 F1F1F1S1F1F1F10 3 CO2 + 8 H2O 
D)  C6H12O6 + 6 O2 F1F1F1S1F1F1F10 6 CO2 + 6 H2O 
E)  2 C6H12O6 + 6 O2 F1F1F1S1F1F1F10 12 CO2 + 6 H2O 
A)  C6H12O6 + O2 F1F1F1S1F1F1F10 CO2 + H2O 
B)  C6H12O6 + 8 O2 F1F1F1S1F1F1F10 6 CO2 + 8 H2O 
C)  C6H12O6 + 12 O2 F1F1F1S1F1F1F10 3 CO2 + 8 H2O 
D)  C6H12O6 + 6 O2 F1F1F1S1F1F1F10 6 CO2 + 6 H2O 
E)  2 C6H12O6 + 6 O2 F1F1F1S1F1F1F10 12 CO2 + 6 H2O

Question 11

Five statements describing water are given below.Which could best be used to explain why water is polar?

Accepted Answer

A)  The water molecule is composed of three atoms held together by two covalent bonds. 
B)  The water molecule contains oxygen and hydrogen. 
C)  The two O-H bonds in water are oriented such that the molecule has a bent shape. 
D)  The oxygen atom is the central atom in a water molecule. 
E)  The two O-H bonds in a water molecule are identical. 
A)  The water molecule is composed of three atoms held together by two covalent bonds. 
B)  The water molecule contains oxygen and hydrogen. 
C)  The two O-H bonds in water are oriented such that the molecule has a bent shape. 
D)  The oxygen atom is the central atom in a water molecule. 
E)  The two O-H bonds in a water molecule are identical.

Question 12

One mole of a substance contains 6.02 × 1023 molecules.This number is known as _______.

Accepted Answer

Question 13

Refer to the balanced chemical equation below. 2 H2 + O2 F1F1F1S1F1F1F10F1F1F1S1F1F1F10 2 H2O + energy
When this reaction occurs, energy is released explosively in the form of heat and light.Based on this information and your knowledge of chemical reactions, which statement is correct?

Accepted Answer

A)  More energy is stored in two H2 and one O2 than is stored in four O-H bonds. 
B)  The sum of the energy of two H2 and one O2 is equal to the sum of the energy of four O-H bonds. 
C)  A water molecule has more stored energy in its bonds than two H2 and one O2 combined. 
D)  Energy is conserved during this reaction, which means that the chemical bond energies in the products are the same as the chemical bond energies in the reactants. 
E)  Energy is observed during this reaction because all chemical reactions involve a release of energy; some reactions just release more than others. 
A)  More energy is stored in two H2 and one O2 than is stored in four O-H bonds. 
B)  The sum of the energy of two H2 and one O2 is equal to the sum of the energy of four O-H bonds. 
C)  A water molecule has more stored energy in its bonds than two H2 and one O2 combined. 
D)  Energy is conserved during this reaction, which means that the chemical bond energies in the products are the same as the chemical bond energies in the reactants. 
E)  Energy is observed during this reaction because all chemical reactions involve a release of energy; some reactions just release more than others.

Question 14

Particles that have a net negative charge are called

Accepted Answer

A)  electronegative. 
B)  cations. 
C)  anions. 
D)  acids. 
E)  bases. 
A)  electronegative. 
B)  cations. 
C)  anions. 
D)  acids. 
E)  bases.

Question 15

What is true about an atom that has no charge?

Accepted Answer

A)  Its nucleus contains neutrons, which are neutral particles. 
B)  Its protons are balanced by an equivalent number of neutrons. 
C)  Its mass depends on the numbers of protons and electrons in its structure. 
D)  It has an even number of electrons. 
E)  It has equal numbers of electrons and protons. 
A)  Its nucleus contains neutrons, which are neutral particles. 
B)  Its protons are balanced by an equivalent number of neutrons. 
C)  Its mass depends on the numbers of protons and electrons in its structure. 
D)  It has an even number of electrons. 
E)  It has equal numbers of electrons and protons.

Question 16

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 17

The six elements most common in organisms are

Accepted Answer

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

Question 18

Oxygen (O) has an atomic number of 8.What is the approximate atomic mass of an oxygen atom in daltons?

Accepted Answer

A)  8 
B)  12 
C)  16 
D)  20 
E)  24 
A)  8 
B)  12 
C)  16 
D)  20 
E)  24

Question 19

Consider the following statement: In a chemical reaction, the properties of the products are usually similar to the reactants.

Accepted Answer

A)  This is true because chemical properties don't change much when chemical partners change. 
B)  This is true because redox reactions don't change the properties. 
C)  This is false because the chemical properties can be significantly altered when chemical partners change. 
D)  This is false because a chemical reaction usually changes the mass of the reactants but not their energy. 
E)  This is false because energy can't be created or destroyed. 
A)  This is true because chemical properties don't change much when chemical partners change. 
B)  This is true because redox reactions don't change the properties. 
C)  This is false because the chemical properties can be significantly altered when chemical partners change. 
D)  This is false because a chemical reaction usually changes the mass of the reactants but not their energy. 
E)  This is false because energy can't be created or destroyed.

Question 20

The reactivity of an atom arises from the

Accepted Answer

A)  energy differences between the orbitals that contain its electrons. 
B)  number of electrons in the outermost electron shell. 
C)  number of electron shells in the atom. 
D)  sum of the potential energies of all electron shells. 
E)  potential energy of the outermost electron shell, or valence shell. 
A)  energy differences between the orbitals that contain its electrons. 
B)  number of electrons in the outermost electron shell. 
C)  number of electron shells in the atom. 
D)  sum of the potential energies of all electron shells. 
E)  potential energy of the outermost electron shell, or valence shell.

Exam 2: Small Molecules and the Chemistry of Life

Two carbon atoms held together in a double covalent bond share _______ electron(s).

The subatomic particles that make up the majority of the mass of an atom are protons and _______.

Refer to the balanced chemical equation below. CH4 + 2 O2  CO2 + 2 H2O + 890 kJ Which graph represents the energy changes accompanying this reaction?

Refer to the figure below showing the chemical structures of several molecules. Which pair of molecules is most likely to be miscible (each soluble in the other)?

The equation C4H10 + 7 O2  4 CO2 + 6 H2O + energy is incorrect because

Differences in the electronegativity of atoms that share electrons in a bond are involved in

Oxygen and carbon are defined as different elements because they have atoms with different numbers of _______ in the nucleus.

The two covalent bonds in a water molecule are polar because

Which equation represents a chemical reaction that obeys the law of conservation of matter?

Five statements describing water are given below.Which could best be used to explain why water is polar?

One mole of a substance contains 6.02 × 1023 molecules.This number is known as _______.

Refer to the balanced chemical equation below. 2 H2 + O2  2 H2O + energy When this reaction occurs, energy is released explosively in the form of heat and light.Based on this information and your knowledge of chemical reactions, which statement is correct?

Particles that have a net negative charge are called

What is true about an atom that has no charge?

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

The six elements most common in organisms are

Oxygen (O) has an atomic number of 8.What is the approximate atomic mass of an oxygen atom in daltons?

Consider the following statement: In a chemical reaction, the properties of the products are usually similar to the reactants.

The reactivity of an atom arises from the

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

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A Changing Biosphere

Filters

Refer to the balanced chemical equation below. CH₄ + 2 O₂ CO₂ +2 H₂O + 890 kJ Which graph represents the energy changes accompanying this reaction?

The equation C₄H₁₀ + 7 O₂ 4 CO₂ + 6 H₂O + energy is incorrect because

One mole of a substance contains 6.02 × 10²³ molecules.This number is known as _______.

Refer to the balanced chemical equation below. 2 H₂ + O₂  2 H₂O + energy When this reaction occurs, energy is released explosively in the form of heat and light.Based on this information and your knowledge of chemical reactions, which statement is correct?

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