48 .
Equal molar amounts of CO and H 2 are sealed in a container and allowed to react
according to the reaction equation above until equilibrium is established. The container is
then compressed, at constant temperature, to half its original volume. Which of the
following statements describes what happens when the container is compressed?(A) When equilibrium is reestablished, all three species have the same partial pressure.
(B) More moles of H 2 (g) are present after compression than before.
(C) The equilibrium constant changes in such a way as to relieve the applied pressure.
When equilibrium is reestablished, the total pressure in the container is the same as
before the compression.(D)
When equilibrium is reestablished, the partial pressure of CH 3 OH (g) is higher than
before compression.(E)
49 . 2 Al (s) + 6 HCl (aq) → 2Al3+ (aq) + 6Cl− (aq) + 3H 2 (g)
The reaction above is best described as a(n)(A) precipitation reaction
(B) acid/base reaction
(C) redox reaction
(D) combustion reaction
(E) decomposition reaction50 . Which change could take place at the anode of an electrochemical cell?
(A) Cu2+ to Cu
(B) ClO 3 − to ClO−
(C) Cl− to Cl 2
(D) H+ to H 2
(E) O 2 to H 2 O