38.A mining company supplies an ore that
is 15.915% chalcocite, Cu 2 S, by weight.
How many metric tons of ore should be
purchased in order to produce 6.0 x 10^2
metric tons of an alloy containing
12.709% Cu?A. 5.0 × 10 –1metric tons
B. 1.0 × 101 metric tons
C. 2.0 × 102 metric tons
D. 3.0 × 102 metric tons
E. 6.0 × 102 metric tons39.At constant temperature and pressure,
the heats of formation of H 2 O(g),
CO 2 (g), and C 2 H 6 (g) (in kilocalories per
mole) are as follows:Species ∆Hf (kcal /mole)
H 2 O(g) −60.0
CO 2 (g) −94.0
C 2 H 6 (g) −20.0If ∆Hvalues are negative for
exothermic reactions, what is ∆H(in
kcal/mole) for 1 mole of C 2 H 6 gas to
oxidize to carbon dioxide gas and water
vapor (same temperature and pressure)?A. −1340.0 kcal/mole
B. −696.0 kcal/mole
C. −348.0 kcal/mole
D. −134.0 kcal/mole
E. 348.0 kcal/mole- Which one of the following is NOT an
assumption of the kinetic theory of
gases?
A. Gas particles are negligibly small.
B. Gas particles undergo a decrease in
kinetic energy when passed from a
region of high pressure to a region
of low pressure.
C. Gas particles are in constant
motion.
D. Gas particles don’t attract each
other.
E. Gas particles undergo elastic
collisions.- How many electrons can be
accommodated in all the atomic orbitals
that correspond to the principal
quantum number 4?
A. 2
B. 8
C. 18
D. 32
E. 40- A linear molecule can have the general
formulas AA, AB, or AB 2. Given a
molecule with the general formula AB 2 ,
which one of the following would be
the most useful in determining whether
the molecule was bent or linear?
A. Ionization energies
B. Electron affinities
C. Dipole moments
D. Electronegativities
E. Bond energiesPart IV: AP Chemistry Practice Test