Question 1

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. A

Question 2

Use the following figure to answer the questions below.
  
-Which drawing in the figure above depicts an atom with a valence of 2?

Accepted Answer

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

Question 3

-In the methane molecule shown in the figure above, bonds have formed that include both the s orbital valence electrons of the hydrogen atoms and the p orbital valence electrons of the carbon. The electron orbitals in these bonds are said to be

Accepted Answer

A) double orbitals. 
B) tetrahedral orbitals. 
C) complex orbitals. 
D) hybrid orbitals. 
E) polar orbitals. 
A) double orbitals. 
B) tetrahedral orbitals. 
C) complex orbitals. 
D) hybrid orbitals. 
E) polar orbitals. D

Question 4

Which of the following would be regarded as compounds?

Accepted Answer

A) H₂O, O₂, and CH₄ 
B) H₂O and O₂ 
C) O₂ and CH₄ 
D) CH₄ and O₂, but not H₂O 
E) H₂O and CH₄, but not O₂ 
A) H₂O, O₂, and CH₄ 
B) H₂O and O₂ 
C) O₂ and CH₄ 
D) CH₄ and O₂, but not H₂O 
E) H₂O and CH₄, but not O₂

Question 5

A covalent chemical bond is one in which

Accepted Answer

A) electrons are removed from one atom and transferred to another atom so that the two atoms become oppositely charged. 
B) protons and neutrons are shared by two atoms so as to satisfy the requirements of both atoms. 
C) outer-shell electrons of two atoms are shared so as to satisfactorily fill the outer electron shells of both atoms. 
D) outer-shell electrons of one atom are transferred to fill the inner electron shell of another atom. 
E) an electron occupies a hybrid orbital located between the nuclei of two atoms. 
A) electrons are removed from one atom and transferred to another atom so that the two atoms become oppositely charged. 
B) protons and neutrons are shared by two atoms so as to satisfy the requirements of both atoms. 
C) outer-shell electrons of two atoms are shared so as to satisfactorily fill the outer electron shells of both atoms. 
D) outer-shell electrons of one atom are transferred to fill the inner electron shell of another atom. 
E) an electron occupies a hybrid orbital located between the nuclei of two atoms.

Question 6

Use the following figure to answer the questions below.
  
-In the figure above, how many unpaired electrons does phosphorus have in its valence shell?

Accepted Answer

A) 15 
B) 2 
C) 3 
D) 7 
E) 5 
A) 15 
B) 2 
C) 3 
D) 7 
E) 5

Question 7

Use the following information to answer the questions below.
You are investigating how chemical reactions occur. You place two reactants together and measure the concentration of product at regular intervals. After a time, the amount of product becomes stable.
-We can represent atoms by listing the number of protons, neutrons, and electrons-for example, 2p⁺; 2n⁰; 2e⁻ for helium. Which of the following represents the ¹⁸O isotope of oxygen?

Accepted Answer

A) 6p⁺, 8n⁰, 6e⁻ 
B) 8p⁺, 10n⁰, 8e⁻ 
C) 9p⁺, 9n⁰, 9e⁻ 
D) 7p⁺, 2n⁰, 9e⁻ 
E) 10p⁺, 8n⁰, 9e⁻ 
A) 6p⁺, 8n⁰, 6e⁻ 
B) 8p⁺, 10n⁰, 8e⁻ 
C) 9p⁺, 9n⁰, 9e⁻ 
D) 7p⁺, 2n⁰, 9e⁻ 
E) 10p⁺, 8n⁰, 9e⁻

Question 8

Use the following figure to answer the questions below.
  
-Which drawing in the figure above depicts the most electronegative atom?

Accepted Answer

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

Question 9

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 10

Use the following information to answer the questions below.
You are investigating how chemical reactions occur. You place two reactants together and measure the concentration of product at regular intervals. After a time, the amount of product becomes stable.
-What coefficients must be placed in the following blanks so that all atoms are accounted for in the products? C₆H₁₂O₆ → ________ C₂H₆O + ________ CO₂

Accepted Answer

A) 1; 2 
B) 3; 1 
C) 1; 3 
D) 1; 1 
E) 2; 2 
A) 1; 2 
B) 3; 1 
C) 1; 3 
D) 1; 1 
E) 2; 2

Question 11

Which one of the atoms shown would be most likely to form a cation with a charge of +1?

Accepted Answer

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

Question 12

Use the following figure to answer the questions below.
  
-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 13

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 14

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 15

Use the following figure to answer the questions below.
  
-Which drawing in the figure above depicts the electron configuration of an element with chemical properties most similar to Helium (2He)?

Accepted Answer

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

Question 16

The nucleus of a nitrogen atom contains 7 neutrons and 7 protons. Which of the following is a correct statement concerning nitrogen?

Accepted Answer

A) The nitrogen atom has a mass number of approximately 7 daltons and an atomic mass of 14. 
B) The nitrogen atom has a mass number of approximately 14 daltons and an atomic mass of 7. 
C) The nitrogen atom has a mass number of 14 and an atomic mass of 7 grams. 
D) The nitrogen atom has a mass number of 7 and an atomic number of 14. 
E) The nitrogen atom has a mass number of 14 and an atomic mass of approximately 14 daltons. 
A) The nitrogen atom has a mass number of approximately 7 daltons and an atomic mass of 14. 
B) The nitrogen atom has a mass number of approximately 14 daltons and an atomic mass of 7. 
C) The nitrogen atom has a mass number of 14 and an atomic mass of 7 grams. 
D) The nitrogen atom has a mass number of 7 and an atomic number of 14. 
E) The nitrogen atom has a mass number of 14 and an atomic mass of approximately 14 daltons.

Question 17

An atom with atomic number 12 would have what type of chemical behaviour in bonding with other elements?

Accepted Answer

A) It would form ions with a +1 charge. 
B) It would form ions with a +2 charge. 
C) It would form ions with a -1 charge. 
D) It would form ions with a -2 charge. 
E) It would form two covalent bonds with other atoms. 
A) It would form ions with a +1 charge. 
B) It would form ions with a +2 charge. 
C) It would form ions with a -1 charge. 
D) It would form ions with a -2 charge. 
E) It would form two covalent bonds with other atoms.

Question 18

-Refer to the figure above (first three rows of the periodic table). If life arose on a planet where carbon were absent, which element might fill the role of carbon?

Accepted Answer

A) boron 
B) silicon 
C) nitrogen 
D) aluminum 
E) phosphorus 
A) boron 
B) silicon 
C) nitrogen 
D) aluminum 
E) phosphorus

Question 19

In ammonium chloride salt (NH₄Cl)the anion is a single chloride ion, Cl. What is the cation of NH₄Cl?

Accepted Answer

A) N, with a charge of +1 
B) NH, with a charge of +1 
C) H₃, with a charge of +1 
D) NH₄, with a charge of +1 
E) NH₄, with a charge of +4 
A) N, with a charge of +1 
B) NH, with a charge of +1 
C) H₃, with a charge of +1 
D) NH₄, with a charge of +1 
E) NH₄, with a charge of +4

Question 20

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

Exam 2: The Chemical Context of Life

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

Use the following figure to answer the questions below. -Which drawing in the figure above depicts an atom with a valence of 2?

-In the methane molecule shown in the figure above, bonds have formed that include both the s orbital valence electrons of the hydrogen atoms and the p orbital valence electrons of the carbon. The electron orbitals in these bonds are said to be

Which of the following would be regarded as compounds?

A covalent chemical bond is one in which

Use the following figure to answer the questions below. -In the figure above, how many unpaired electrons does phosphorus have in its valence shell?

Use the following figure to answer the questions below. -Which drawing in the figure above depicts the most electronegative atom?

Which of the following statements is false?

Which one of the atoms shown would be most likely to form a cation with a charge of +1?

Use the following figure to answer the questions below. -What results from the chemical reaction illustrated above?

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

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

Use the following figure to answer the questions below. -Which drawing in the figure above depicts the electron configuration of an element with chemical properties most similar to Helium (2He)?

The nucleus of a nitrogen atom contains 7 neutrons and 7 protons. Which of the following is a correct statement concerning nitrogen?

An atom with atomic number 12 would have what type of chemical behaviour in bonding with other elements?

-Refer to the figure above (first three rows of the periodic table). If life arose on a planet where carbon were absent, which element might fill the role of carbon?

In ammonium chloride salt (NH₄Cl)the anion is a single chloride ion, Cl. What is the cation of NH₄Cl?

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

Introduction: Evolution and Themes of Biology

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

Dna Tools and 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 Signalling

Nervous Systems

Sensory and Motor Mechanisms

Animal Behaviour

An Introduction to Ecology and the Biosphere

Population Ecology

Community Ecology

Ecosystems and Restoration Ecology

Conservation Biology and Global Change

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