AP Chemistry
UNIT 3 QUIZ
Name:______________
1.) (15pts) Using effective nuclear charge, explain the trends for:
a. electronegativity
b. ionization energy
c. atomic radius
2.) (5pts) Explain reactivity for metals and nonmetals using the four trends
listed above.
3.) (5pts) Why is the 1st ionization energy lower for boron than beryllium?
4.) (5pts) Calculate the Zeff using Slater’s rules for a valence electron in Cr. (Show
all work).
AP Chemistry
UNIT 3 QUIZ
Name:______________
1.) 1979 D (20pts)
Butane, chloroethane, acetone, and 1-propanol all have approximately the same
molecular weights. Data on their boiling points and solubilities in water are listed in the
table below.
Compound
Butane
Formula
CH3CH2CH2CH3
Chloroethane
CH3CH2Cl
Acetone
CH3C
CH3
Boiling
Pt.(ºC)
0
12
56
Solubility
in water
insoluble
insoluble
completely
miscible
completely
miscible
1-Propanol CH3CH2CH2OH
97
On the basis of dipole moments (molecular polarities) and/or hydrogen bonding, explain in a
qualitative way the differences in the
(a) boiling points of butane and chloroethane.
(b) water solubilities of chloroethane and acetone.
(c) water solubilities of butane and 1-propanol.
(d) boiling points of acetone and 1-propanol.
AP Chemistry
UNIT 3 QUIZ
Name:______________
2.) 1982 D (30pts)
(a) Draw the Lewis electron-dot structures for CO32-, CO2, and CO, including
hybridization, molecular geometry, formal charges and resonance structures where
appropriate.
(b) Which of the three species has the shortest C-O bond length? Explain the reason for
your answer.
2.) (20pts) Use MO diagrams N2 and O2 to explain which if either would be attracted
by a magnet.
a.) What happens to the bond order if an electron is added to each molecule?
AP Chemistry
UNIT 3 QUIZ
Name:______________
Take Home Portion of UNIT Quiz: Due Monday.
1.) (30pts) Assume that you have two different gases that you know are not cyclic (i.e.
not ring) compounds, each with the following elementary analysis: C = 85.7%, H =
14.3%. Each gas has a molecular weight of 56.
(a) What is the molecular formula for the compounds?
(b) Draw the structural formulas for the four possible noncyclic isomers with this
molecular formula.
(c) In the presence of an appropriate catalyst, both gases add hydrogen. The
hydrogenated products are identical, their molecular weight is 58. Which of the
structures you drew to answer (b) can definitely be eliminated on the basis of this
additional information?
2.) (10pts) What is meant by the lanthanide contraction? Account for this phenomenon.
Give two examples of its consequences.
AP Chemistry
UNIT 3 QUIZ
Name:______________
3.) (10pts) Predict the molecule in the mass spec spectra below. Label each peak.
4.) (20pts) Draw an MO diagram for HCl. Predict the PES specta that would be
produced by this compound.