Question 1

Elements ⁷²Zn, ⁷⁵As, and ⁷⁴Ge have the ________.

Accepted Answer

A)   same number of protons
B)   same number of protons and electrons
C)   same number of neutrons
D)   same number of neutrons and electronsE) B) and C)
F) A) and D) C

Question 2

Trace elements are those required by an organism in only minute quantities. Which of the following is a trace element that is required by humans and other vertebrates, but not by other organisms such as bacteria or plants?

Accepted Answer

A)   calcium
B)   iodine
C)   sodium
D)   phosphorusE) A) and C)
F) All of the above

Question 3

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

Question 4

a(n. ________ has charge but negligible mass, whereas a(n)  ________ has mass but no charge.

Accepted Answer

A)   proton; neutron
B)   neutron; proton
C)   neutron; electron
D)   electron; neutronE) B) and D)
F) C) and D)

Question 5

When are atoms most stable?

Accepted Answer

A)   when they have the fewest possible valence electrons
B)   when they have the maximum number of unpaired electrons
C)   when all of the electron orbitals in the valence shell are filled
D)   when all electrons are pairedE) B) and C)
F) B) and D)

Question 6

In the following structure where A and B represent two different elements, the valency of A is ________ and B is ________.

Accepted Answer

A)   one; three
B)   one; five
C)   three; five
D)   eight; eightE) B) and C)
F) A) and B)

Question 7

About 25 of the 92 natural elements are known to be essential to life. Which 4 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, oxygenE) B) and D)
F) C) and D)

Question 8

An ion with six protons, seven neutrons, and a charge of 2+ has an atomic number of ________.

Accepted Answer

A)   four
B)   five
C)   six
D)   sevenE) C) and D)
F) A) and B) C

Question 9

Compared with ³¹P, the radioactive isotope ³²P has

Accepted Answer

A)   a different atomic number.
B)   one more proton.
C)   one more electron.
D)   one more neutron.E) B) and C)
F) A) and B)

Question 10

Can the atomic mass of an element vary?

Accepted Answer

A)   No, it is fixed; otherwise a new element will be formed.
B)   Yes. Adding or losing electrons will substantially change the atomic mass.
C)   Yes. Adding or losing protons will change the atomic mass without forming a different element.
D)   Yes. Adding or losing neutrons will change the atomic mass without forming a different element.E) B) and C)
F) A) and B)

Question 11

Molybdenum has an atomic number of 42. Several common isotopes exist, with mass numbers from 92-100. Which of the following can be true?

Accepted Answer

A)   Molybdenum atoms can have between 50 and 58 neutrons.
B)   Molybdenum atoms can have between 50 and 58 protons.
C)   Molybdenum atoms can have between 50 and 58 electrons.
D)   Isotopes of molybdenum have different numbers of electrons.E) C) and D)
F) All of the above

Question 12

Which of the following are compounds?

Accepted Answer

A)   H₂O, O₂, and CH₄
B)   H₂O and O₂
C)   O₂ and CH₄
D)   H₂O and CH₄, but not O₂E) A) and B)
F) A) and C)

Question 13

Carbon-14 has the same ________.

Accepted Answer

A)   atomic number and atomic mass as carbon-12
B)   atomic number and thus number of neutrons as carbon-13
C)   atomic mass as both carbon-12 and carbon-13
D)   number of protons but more neutrons than carbon-12E) None of the above
F) A) and B)

Question 14

Refer to the following figure to answer the questions below.
 
-When the atoms involved in a covalent bond have the same electronegativity, what type of bond results?

Accepted Answer

A)   an ionic bond
B)   a hydrogen bond
C)   a nonpolar covalent bond
D)   a polar covalent bondE) A) and B)
F) C) and D)

Question 15

Refer to the following figure to answer the questions below.
 
-How many electrons will a single atom of sulfur with no charge and no bonds have in its valence shell?

Accepted Answer

A)   6
B)   8
C)   16
D)   32E) B) and C)
F) A) and C)

Question 16

Refer to the following figure to answer the questions below.
3H₂ + N₂  2NH₃
-Which of the following is true for the reaction?

Accepted Answer

A)   The reaction is nonreversible.
B)   Hydrogen and nitrogen are the reactants of the reverse reaction.
C)   Ammonia is being formed and decomposed simultaneously.
D)   Only the forward or reverse reactions can occur at one time.E) A) and B)
F) None of the above C

Question 17

Refer to the following figure to answer the questions below.
 
-Oxygen has an atomic number of 8 and, most commonly, a mass number of 16. Thus, what is the atomic mass of an oxygen atom?

Accepted Answer

A)   approximately 8 grams
B)   approximately 8 daltons
C)   approximately 16 grams
D)   approximately 16 daltonsE) A) and D)
F) All of the above

Question 18

Refer to the following figure to answer the questions below.
 
-What is the atomic number of the cation formed in the reaction in the illustration?

Accepted Answer

A)   8
B)   10
C)   11
D)   16E) B) and C)
F) C) and D)

Question 19

Atoms have no electric charge because they have ________.

Accepted Answer

A)   uncharged neutrons in their nuclei
B)   an equal number of protons and neutrons
C)   an equal number of protons and electrons
D)   an equal number of charged and uncharged subatomic particlesE) C) and D)
F) A) and B)

Question 20

Which bond or interaction would be difficult to disrupt when compounds are put into water?

Accepted Answer

A)   covalent bonds between carbon atoms
B)   hydrogen bonds
C)   ionic bonds
D)   ionic and hydrogen bondsE) All of the above
F) A) and C)

Exam 2: The Chemical Context of Life

Elements ⁷²Zn, ⁷⁵As, and ⁷⁴Ge have the ________.

Correct AnswerverifiedC

Trace elements are those required by an organism in only minute quantities. Which of the following is a trace element that is required by humans and other vertebrates, but not by other organisms such as bacteria or plants?

Correct AnswerverifiedShow Answer

What coefficients must be placed in the following blanks so that all atoms are accounted for in the products? C₆H₁₂O₆ → ________ C₂H₆O + ________ CO₂

Correct AnswerverifiedShow Answer

a(n. ________ has charge but negligible mass, whereas a(n) ________ has mass but no charge.

Correct AnswerverifiedShow Answer

When are atoms most stable?

Correct AnswerverifiedShow Answer

In the following structure where A and B represent two different elements, the valency of A is ________ and B is ________.

Correct AnswerverifiedShow Answer

About 25 of the 92 natural elements are known to be essential to life. Which 4 of these 25 elements make up approximately 96% of living matter?

Correct AnswerverifiedShow Answer

An ion with six protons, seven neutrons, and a charge of 2+ has an atomic number of ________.

Correct AnswerverifiedC

Compared with ³¹P, the radioactive isotope ³²P has

Correct AnswerverifiedShow Answer

Can the atomic mass of an element vary?

Correct AnswerverifiedShow Answer

Molybdenum has an atomic number of 42. Several common isotopes exist, with mass numbers from 92-100. Which of the following can be true?

Correct AnswerverifiedShow Answer

Which of the following are compounds?

Correct AnswerverifiedShow Answer

Carbon-14 has the same ________.

Correct AnswerverifiedShow Answer

Refer to the following figure to answer the questions below. -When the atoms involved in a covalent bond have the same electronegativity, what type of bond results?

Correct AnswerverifiedShow Answer

Refer to the following figure to answer the questions below. -How many electrons will a single atom of sulfur with no charge and no bonds have in its valence shell?

Correct AnswerverifiedShow Answer

Refer to the following figure to answer the questions below. 3H₂ + N₂ 2NH₃ -Which of the following is true for the reaction?

Correct AnswerverifiedC

Refer to the following figure to answer the questions below. -Oxygen has an atomic number of 8 and, most commonly, a mass number of 16. Thus, what is the atomic mass of an oxygen atom?

Correct AnswerverifiedShow Answer

Refer to the following figure to answer the questions below. -What is the atomic number of the cation formed in the reaction in the illustration?

Correct AnswerverifiedShow Answer

Atoms have no electric charge because they have ________.

Correct AnswerverifiedShow Answer

Which bond or interaction would be difficult to disrupt when compounds are put into water?

Correct AnswerverifiedShow Answer

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C

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What coefficients must be placed in the following blanks so that all atoms are accounted for in the products? C₆H₁₂O₆ → C₂H₆O + CO₂

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a(n. has charge but negligible mass, whereas a(n) has mass but no charge.

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In the following structure where A and B represent two different elements, the valency of A is and B is .

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C

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C

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