Student ID: _________________________
Mock Exam 1A
Multiple choice (5 percent each, no partial credit)
1. Which statements are false?
X. The nucleus accounts for most of the atom’s mass (or weight)
Y. According to the atomic theory, all matter is composed of neutrons
Z. Most of an atom is empty space
a. Y only
b. Y and Z
c. X and Y
d. X only
e. X and Z
2. Which list contains a transition metal, a halogen and an alkali metal (in any order)?
a. Cs, Ni, At
b. K, F, Ne
c. Fe, Li, Se
d. Mg, Co, Cl
e. Au, Na, Al
3. Removing 21 electrons, 21 protons, and 20 neutrons from 84Sr gives what?
a. 43Ar
b. 43Cl
c. None of the others
d. 43Ar+
e. 41Sc
4. Which statements are false?
X. Alkali metals are the most reactive metals.
Y. To achieve a noble-gas electron configuration, halogens tend to gain 2 electrons.
Z. Metalloids are lustrous like metals.
a. X and Z
b. X only
c. Y and Z
d. Z only
e. Y only
5. Use the table below to find the atomic weight of a sample of osmium.
Isotope
188
Os
Os
190
Os
189
Isotopic
mass (u)
189.5
190.5
191.5
Percent
abundance
15.52%
16.18%
26.41%
192
Os
193.6
41.89%
a. 191.3 amu
b. 191.9 amu
c. 190.2 amu
d. 189.8 amu
e. 190.4 amu
6. Calculate the isotopic mass for 207Ra.
a. 208.628 amu
b. None of the others
c. 207.000 amu
d. 226.000 amu
e. 208.671 amu
7. Which statements are false?
X. The ionic radius of a cation is always larger than the atomic radius of the neutral atom
Y. Isoelectronic ions have the same electron configuration
Z. The atomic radii of transition metal atoms continuously decrease as you go from left-to-right
along a row.
a. X only
b. Y only
c. Z only
d. X and Y
e. X and Z
8. Predict the order from smallest to largest for the following set of atoms
Bi
P
Se S
As
a. Bi, P, Se, S, As
b. None of the others
c. Bi, Se, As, S, P
d. P, Se, S, As, Bi
e. P, S, As, Se, Bi
9. Predict the order from largest to smallest for the following set of ions
Br-
Ca2+ K+
As3-
Se2-
a. Ca2+, K+, Br-, Se2-, As3b. K+, Ca2+, As3-, Se2-, Brc. Br-, Se2-, As3-, Ca2+, K+
d. None of the others
e. As3-, Se2-, Br-, K+, Ca2+
10. Which of the following is the correct electron configuration for Al using noble-gas notation?
a. [He]2s22p63s23p1
b. [Ne]3s23p1
c. [Mg]3p1
d. None of the others
11.
12.
13.
14.
15.
e. 1s22s22p63s23p1
Which is the correct electron configuration for Cu2+ using noble-gas notation?
a. [Ar]4s13d10
b. [Ar]4s23d7
c. None of the others
d. [Ar]3d9
e. [Ar]4s13d8
Calculate the wavelength of light required to excite an electron in a hydrogen atom from the n = 2
state to the n = 5 state.
a. 4.34 × 10-7 m
b. 6.56 × 10-7 m
c. 4.86 × 10-7 m
d. 4.10 × 10-7 m
e. 1.22 × 10-7 m
Calculate the de Broglie wavelength of a neutron moving at 50 m/s. The mass of a neutron is 1.6749
× 10-24 g.
a. None of the others
b. 1.26 × 108 m
c. 7.91 × 10-9 m
d. 1.26 × 1011 m
e. 7.91 × 10-12 m
Which statements are true?
X. Single bonds are formed when atoms share 6 electrons.
Y. The octet rule states that main group atoms gain, share of lose electrons to achieve an octet in
their valence shells.
Z. Lewis structures represent valence electrons as dots or as lines.
a. Y and Z
b. X and Z
c. X and Y
d. X only
e. Z only
Which of the following atoms would you predict to have the highest first ionization energy?
a. Cs
b. Sr
c. Ga
d. Ar
e. Se
Fill-in-the-blank (1 percent each, no partial credit)
Write legibly. Unreadable answers will be counted wrong.
16. Either write the compound name or write the molecular formula.
Compound name
Molecular formula
P4O10
Nitrous oxide
SiO2
Hydrazine
SF4
Short Answer (5 percent each, no partial credit)
17. Draw the Lewis structure for N2H4. If the molecule needs resonance structures, then include all of
them.
18. Draw the Lewis structure for NO2. If the molecule needs resonance structures, then include all of
them.
19. Draw the energy level diagram for nitrogen and indicate whether it is paramagnetic or diamagnetic.
20. Sketch the orbital indicated and label your axes. You’ll be graded on the shape, orientation, shading
and relative size.
3dz2
Useful information
Mass of a proton = 1.00728 u
Mass of a neutron = 1.00866 u
Speed of light: c = 2.998 × 108 m/s
Planck’s constant: h = 6.626 × 10-34 J·s
Equation for hydrogen atom energy levels