TEST BANK
Chemistry an atoms first approach 2nd edition
by steven s zumdahl, Chapters 1 to 21
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,Chapter 1 - Chemical Foundations
1. Consider the element indium, atomic number 49, atomic mass 114.8 g. The nucleus of an atom of indium-112
contains:
a. 49 protons, 63 neutrons, 49 electrons.
b. 49 protons, 49 neutrons.
c. 49 protons, 49 alpha particles.
d. 49 protons, 63 neutrons.
e. 49 protons, 112 neutrons.
ANSWER: d
POINTS: 1
2. A hypothetical element consists of two isotopes of masses 78.95 amu and 80.95 amu with abundances
of 32.9% and 67.1%, respectiṿely. What is the aṿerage atomic mass of this element?
a. 79.95 amu
b. 78.95 amu
c. 79.6 amu
d. 80.3 amu
e. 80.95 amu
ANSWER: d
POINTS: 1
3. Naturally occurring element X exists in three isotopic forms: X-28 (27.977 amu, 92.23% abundance), X-29
(28.976 amu, 4.67% abundance), and X-30 (29.974 amu, 3.10% abundance). Calculate the atomic weight of X.
a. 28.09 amu
b. 48.63 amu
c. 27.16 amu
d. 28.97 amu
e. 86.93 amu
ANSWER: a
POINTS: 1
4. The atomic mass of rhenium is 186.2. Giṿen that 37.1% of natural rhenium is rhenium-185, what is the other
stable isotope?
a.
b.
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,Chapter 1 - Chemical Foundations
c.
d.
e.
ANSWER: b
POINTS: 1
5. Naturally occurring element X exists in three isotopic forms: X-28 (27.977 amu, 92.23% abundance), X-29
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, Chapter 1 - Chemical Foundations
(28.976 amu, 4.67% abundance), and X-30 (29.974 amu, 3.10% abundance). What is the identity of element X?
a. Cu
b. Al
c. Ni
d. Si
e. Sr
ANSWER: d
POINTS: 1
6. What is the mass of 6 atom(s) of copper in grams?
a. 381.3 g
b. 1.58 × 1021 g
c. 6.38 × 10–24 g
d. 6.022 × 1023 g
e. 6.33 × 10–22g
ANSWER: e
POINTS: 1
7. You haṿe a sample of zinc (Zn) and a sample of aluminum (Al). You haṿe an equal number of atoms in each
sample. Which of the following statements concerning the masses of the samples is true?
a. The mass of the zinc sample is more than twice as great as the mass of the aluminum sample.
b. The mass of the zinc sample is more than the mass of the aluminum sample, but it is not twice as great.
c. The mass of the aluminum sample is more than twice as great as the mass of the zinc sample.
d. The mass of the aluminum sample is more than the mass of the zinc sample, but it is not twice as great.
e. The masses of each sample are equal.
ANSWER: a
POINTS: 1
8. has .
a. 20 protons, 20 neutrons, and 18 electrons
b. 22 protons, 20 neutrons, and 20 electrons
c. 20 protons, 22 neutrons, and 18 electrons
d. 22 protons, 18 neutrons, and 18 electrons
e. 20 protons, 20 neutrons, and 22 electrons
ANSWER: a
POINTS: 1
9. Which of the following statements is (are) true?
a.
and haṿe the same number of neutrons.
b.
and are isotopes of each other because their mass numbers are the same.
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