Question 1

He has the same number of valence electrons as _____.

Accepted Answer

A)  H 
B)  Ne 
C)  F 
D)  Na

Question 2

Determine the number of atoms in a copper strip that has a mass of 35.0 grams.

Accepted Answer

A)  3.33 × 1025 atoms 
B)  2.11 × 1025 atoms 
C)  2.71 × 1020 atoms 
D)  3.32 × 1023 atoms 
E)  0.551 atoms

Question 3

Calculate the number of moles in a 25.0 g sample of carbon.

Accepted Answer

A)  2.08 moles 
B)  13.0 moles 
C)  300 moles 
D)  1.51 × 1025 moles 
E)  3.33 × 10-  3  moles

Question 4

Which of these elements is not a transition metal?

Accepted Answer

A)  Cu 
B)  Fe 
C)  Na 
D)  Ag 
E)  Hg

Question 5

An element has two naturally occurring isotopes. One has an abundance of 37.4% and an isotopic mass of 184.953 amu. The other has an abundance of 62.6% and an isotopic mass  of 186.956 amu. What is the atomic weight of the element?

Accepted Answer

A)  185.702 amu 
B)  185.954 amu 
C)  186.207 amu 
D)  186.956 amu 
E)  190.234 amu

Question 6

Neon has three isotopes. Assuming the mass of each isotope to be very close to its respective mass number, which isotope is the most abundant based on the atomic mass of neon (Ne)?

Accepted Answer

A)  Ne-20 
B)  Ne-21 
C)  Ne-22 
D)  The question lacks sufficient data. 
E)  The abundance of an isotope is independent of the mass number of neon.

Question 7

Which of these elements has seven valence electrons?

Accepted Answer

A)  Mg 
B)  Li 
C)  Al 
D)  S 
E)  Cl

Question 8

Calculate the number of moles of lead in a 442-gram lead anvil.

Accepted Answer

A)  0.468 moles 
B)  2.13 moles 
C)  96.97 moles 
D)  6.022 × 1023 moles 
E)  1.28 × 1024 moles

Question 9

What are the Z and A values for an atom of krypton that contains 46 neutrons?

Accepted Answer

A)  Z=36, A=46 
B)  Z=46, A=36 
C)  Z=36, A=82 
D)  Z=82, A=36 
E)  Z=82, A=46

Question 10

What is the correct number of atoms in one mole of neon?

Accepted Answer

A)  10 
B)  3.011 x 1023 
C)  6.022 × 1023 
D)  20 
E)  12

Question 11

Which of these is the correct chemical symbol for carbon?

Accepted Answer

A)  C 
B)  Ca 
C)  Cl 
D)  Cb 
E)  Co

Question 12

Determine the correct number of protons and electrons in P  3 −  .

Accepted Answer

A)  3 protons and 6 electrons 
B)  15 protons  and  18 electrons 
C)  15 protons  and  12 electrons 
D)  31 protons  and  28 electrons 
E)  31 protons  and  34 electrons

Question 13

Which scientist is responsible for the organization of the modern periodic table?

Accepted Answer

A)  Bohr 
B)  Galileo 
C)  Dalton 
D)  Avogadro 
E)  Mendeleev

Question 14

The mass of which of the following is the least?

Accepted Answer

A)  A proton 
B)  A neutron 
C)  An electron 
D)  A hydrogen atom 
E)  A hydrogen nucleus

Question 15

Determine the mass of one mole of silver.

Accepted Answer

A)  107.87 amu 
B)  107.87 g 
C)  47 amu 
D)  47 g 
E)  6.022 × 1023 amu

Question 16

Which of these is not equivalent to one mole?

Accepted Answer

A)  6.022 × 1023 marbles 
B)  12 grams of carbon 
C)  Avogadro's number 
D)  12 grams of magnesium 
E)  28 grams of nitrogen, N2

Question 17

The Ca2+ ion contains _____ protons and _____ electrons.

Accepted Answer

A)  20; 20 
B)  20; 22 
C)  22; 20 
D)  18; 20 
E)  20; 18

Question 18

Radon - 222 has _____ protons, _____ neutrons, and _____ electrons.

Accepted Answer

A)  86; 86; 86 
B)  86; 222; 86 
C)  86; 136; 86 
D)  86; 136; 222 
E)  86; 222; 308

Question 19

Metals tend to _____ electrons to form ions of _____ charge.

Accepted Answer

A)  lose; negative 
B)  lose; positive 
C)  gain; positive 
D)  gain; negative 
E)  gain; neutral

Question 20

Which of these is the correct chemical symbol for cobalt?

Accepted Answer

A)  C 
B)  Cl 
C)  Co 
D)  Ca 
E)  Ce

Exam 3: Atoms and Elements