CHEMISTRY 1201, Lecture section 02 and 03
SAMPLE EXAM 2 - SPRING
2002 - Answers
PART 1 - Multiple Choice
1. The wavelength of radiation from
a cellular telephone, which emits at a frequency of 879 MHz is?
a) 2.93 m
b) 2.93 x 10-8 m
c) 34.1 m
d) 341 m
e) 3.4 x 10-1 m
2. The energy of a photon with a wavelength
of 400 nm is?
a) 4.97 x 10-28J
b) 4.97 x 10-19J
c) 1.33 x 10-15J
d) 7.5 x 105J
e) 7.5 x 1014J
3. The sole electron in a H atom undergoes
a transition from n = 3 to n = 1. Which TWO statements are true?
a) energy is lost by the atom
b) energy is gained by the atom
c) a photon of radiant energy is absorbed
d) a photon of radiant energy is emitted
e) none of the above
4. Which of the statements concerning
the quantum mechanical description is FALSE?
a) Orbitals have no physical meaning with respect
to the atom, they are merely mathematical entities.
b) Electrons exhibit both wave and particle properties.
c) The square of the wavefunction allows one
to define the electron probability distribution within an atom.
d) Electrons inhabit circular orbits.
e) Electromagnetic radiation exhibits both wave
and particle properties.
5. Which of the following sets of quantum
numbers ARE ALLOWED?
a) n = 0, l = 0, ml = 0
b) n = 1, l = 0, ml = 0
c) n = 2, l = 1, ml = -2
d) n = 6, l = 5, ml = -5
e) n = 6, l = -4, ml = 5
6. Consider a balloon picture for a
2pz (Fig. 6.22b left). Identify which of the following statements
is FALSE.
a) There is a zero probability of finding an electron
on the nucleus.
b) There is a 90% probability of the electrons
in this orbital being located within the balloon.
c) Electrons in this orbital are always located
somewhere on the surface of the balloon.
d) The largest probability of finding an electron
in this orbital is along the z axis.
e) Only two electron may inhabit the 2pz
orbital.
Answer the next four questions using the
information given below:
7. Identify the electron configuration
that violates Hund's rule:
.
8. Identify the electron configuration
that violates Pauli's Exclusion Principle:
.
9. Identify the valence electron configuration
for Se2-:
.
10. Which of the electron configurations
is completely ridiculous?:
.
11. Identify which of the following
statements concerning ionization energy (I) is FALSE.
a) Ionization energy increases in the order I1
< I2 < I3.
b) Ionization energy is the energy required to
remove an electron from a solid atom or ion.
c) Some of the largest differences in ionization
energies occur when going from removing valence electrons to removing core
electrons.
d) First ionization energy decreases going down
a group.
e) none of the above.
12. Identify which of the following
statements concerning atomic radii is FALSE.
a) Atomic radii increase going down a group because
of the increase in orbital sizes and a successive increase in the outermost
principle quantum level.
b) The atomic radius is only an estimation of
the actual size of an atom.
c) Atomic radii are often called bonding radii
as they are determined from the distances between atoms that are covalently
bonded to one another.
d) Atomic radii decrease going right to left
in the periodic table because of an increase in Zeff.
e) none of the above.
13. The polarity of a covalent bond
can be estimated using the electronegativity differences between the atoms
involved in that bond.
a) true
b) false
14. Place the bonds, C-H, O-H and H-H
in order of decreasing bond polarity.
a) H-H > C-H > O-H
b) O-H > H-H > C-H
c) O-H > C-H > H-H
d) C-H > O-H > H-H
e) H-H > O-H > C-H
15. Identify a set of isoelectronic
atoms/ions.
a) Na+, Mg 2+, S 2-,
Cl -, Ar
b) F
-, Cl -, Br -,
I -, At -
c) Ca
2+, K +, Ar, Cl -,
S 2-
d) Fe
2+, Co 2+, Ni 2+,
Cu 2+, Zn
2+
e) none of the above
16. Electronegativity differences can
be tentatively used to predict whether an ionic or a covalent bonding will
occur between atoms.
a) true
b) false
PART 2 - Written Question
17. a) Draw balloon picture of a dx2-y2
orbital.
b) Give an example of an element with an electron
configuration in which all five 3d orbitals are occupied with at least
one electron each.