Equilibrium ❮ 235- CH 4 (g) + CO 2 (g) ^ 2 CO(g) + 2 H 2 (g)
A 1.00 L flask is filled with 0.30 mole of CH 4
and 0.40 mole of CO 2 and allowed to come to
equilibrium. At equilibrium, there are 0.20 mole
of CO in the flask. What is the value of Kc, the
equilibrium constant, for the reaction?
(A) 1.2
(B) 0.027
(C) 0.30
(D) 0.060
- 2 NO 2 (g) ^ 2 NO(g) + O 2 (g)
The above materials were sealed in a flask and
allowed to come to equilibrium at a certain tem-
perature. A small quantity of O 2 (g) was added to
the flask, and the mixture was allowed to return
to equilibrium at the same temperature. Which
of the following has increased over its original
equilibrium value?
(A) the quantity of NO 2 (g) present
(B) the quantity of NO(g) present
(C) the equilibrium constant, K, increases
(D) the rate of the reaction
- 2 CH 4 (g) + O 2 (g) ^ 2 CO(g) + 4 H 2 (g) ΔH < 0
To increase the value of the equilibrium con-
stant, K, which of the following changes must be
made to the above equilibrium?
(A) increase the temperature
(B) increase the volume
(C) decrease the temperature
(D) add CO(g)
- The addition of nitric acid increases the solubility
of which of the following compounds?
(A) KCl(s)
(B) Pb(CN) 2 (s)
(C) Cu(NO 3 ) 2 (s)
(D) NH 4 NO 3 (s) - At constant temperature, a change in the volume
of the system will NOT affect the moles of the
substances present in which of the following?
(A) C(s) + H 2 O(g) ^ H 2 (g) + CO(g)
(B) 3 O 2 (g) ^ 2 O 3 (g)
(C) Xe(g) + 2 F 2 (g) ^ XeF 4 (g)
(D) 6 CO 2 (g) + 6 H 2 O(l) ^ 6 O 2 (g) + C 6 H 12 O 6 (aq)
22. Which of the following is the strongest Brønsted–
Lowry acid?
(A) HBrO
(B) HBrO 3
(C) HBrO 2
(D) HBrO 4
23. Ionization Constants
NH 3 Kb = 1.8 × 10 -^5
CH 3 NH 2 Kb = 4.4 × 10 -^4
(CH 3 ) 2 NH Kb = 1.1 × 10 -^3
How would a solution with an initial NH 4 Cl
(NH 4 + + Cl-) concentration of 1 M and an initial
CH 3 NH 3 Cl (CH 3 NH 3 + + Cl-) concentration of
1 M be classified?
(A) a solution with a pH > 7, which is a buffer
(B) a solution with a pH < 7, which is not a
buffer
(C) a solution with a pH < 7, which is a buffer
(D) a solution with a pH > 7, which is not a
buffer
24. Which of the following species CANNOT serve
as both a Brønsted base and a Brønsted acid?
(A) H 2 PO 42 -
(B) CO 32 -
(C) HSeO 4 -
(D) HCO 3 -
25. A chemistry student adds some dilute ammonia
solution to some insoluble silver chloride. The
solid dissolves. Which of the following is the cor-
rect net ionic equation for the reaction?
(A) AgCl + 2 NH 3 → [Ag(NH 3 ) 2 ]+ + Cl-
(B) AgCl + 2 NH 4 +→ [Ag(NH 4 ) 2 ]^3 + + Cl-
(C) AgCl + NH 4 +→ Ag++ NH 4 Cl
(D) AgCl + NH 3 → Ag++ NH 3 Cl
26. Which of the following contains only equilibria
that are normally always homogeneous?
(A) Ka, Kb, and Ksp
(B) Ka, Ksp, and Kf
(C) Ka, Kb, and Kf
(D) Ksp, Kb, and Kf