These questions have been provided on a CC-BY basis to facilitate peer instruction.

1. The Group 15 flip

2. Why share questions?
• There are many excellent open
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• These include many videos of
more-or-less traditional university
lecturing.
• These questions have been
provided on a CC-BY basis to
facilitate peer instruction.

3. Why are the H-N-H bond
angles in ammonia and
ammonium different?
A. Different number
of electron pairs
around nitrogen
B. They are the same!
C. Lone pairs repel
more strongly than
bonding pairs
D. Ones an ion, the
other a molecule
Differentnum
berofelec...Theyare
the
sam
e!
Lone
pairsare
m
ore
repul...
Differentcharge
on
the...
0% 0%0%0%

4. How can we use reduction
potentials to predict reactivity?
Couple E0
Au+ + e− → Au +1.69 V
[NO3]− + 4H+ + 3e− → NO + 2H2O +0.96 V
Cu2+ + 2e− → Cu +0.34 V
2H+ + 2e− → H2 0.0 V
Zn2+ + 2e− → Zn -0.76 V
Mg2+ + 2e− → Mg -2.37 V
• Note: Strictly, standard reduction potentials are
expressed for a single electron, but since the value is
intrinsic the potential will not change.

5. Which of the following metals
will react with nitric acid but
not protons?
1. Gold
2. Zinc
3. Magnesium
4. Copper
Gold
Zinc
M
agnesium
Copper
0% 0%0%0%

6. Which of the following is a factor in
explaining the greater stability of
polyatomic versus diatomic allotropes of
phosphorus under ambient conditions?
A. Entropy
B. The dependence of the
number of p orbitals on
atomic number
C. The relatively low
reactivity of oligomeric
allotropes of phosphorus
D. The dependence of lone
pair repulsion and p
orbital overlap on
atomic size
Entropy
Thedependence
ofthe
...
Therelativelylow
reactivi..
Thedependence
oflone
...
0% 0%0%0%

7. What species would you expect to
predominate if you raise the pH of a solution
of phosphoric acid to between 7 and 12?
A. H3PO4
B. [H2PO4]−
C. [HPO4]2−
D. [PO4]3−