Chemical Equilibrium and Ionic Equilibrium - One Line Questions
1.
For a general reversible reaction aA + bB <=> cC + dD, the equilibrium constant Kc is expressed as: —
([C]^c [D]^d) / ([A]^a [B]^b)
2.
For a weak base BOH, the base dissociation constant Kb is defined as: —
([B+][OH-]) / [BOH]
3.
For a weak acid HA, the acid dissociation constant Ka is defined as: —
([H+][A-]) / [HA]
4.
The solubility product constant (Ksp) for a sparingly soluble salt like CaF2(s) <=> Ca2+(aq) + 2F-(aq) is expressed as: —
[Ca2+][F-]^2
5.
For the dissociation of water, H2O <=> H+ + OH-, the ion product constant Kw is: —
[H+][OH-]
6.
The pOH of a 0.01 M NaOH solution is: —
2
7.
The pKa of a weak acid is 4.74. If the pH of the solution is 5.04, what is the ratio of [A-]/[HA]? —
2:1
8.
A solution with pH = 2 is how many times more acidic than a solution with pH = 3? —
10 times
9.
Which of the following is an example of homogeneous equilibrium? —
H2(g) + I2(g) <=> 2HI(g)
10.
If Kc = 1.6 x 10^-5 for the reaction H2O(l) <=> H+(aq) + OH-(aq), what is the pH of pure water at this temperature? —
3.5
11.
The common ion effect describes the decrease in solubility of an ionic compound when it is dissolved in a solution that already contains: —
A common ion.
12.
According to Arrhenius theory, an acid is a substance that: —
Produces H+ ions in aqueous solution.
13.
Hydrolysis of salts of strong acid and weak base results in a solution that is: —
Basic
14.
Which of the following is a Lewis base? —
NH3
15.
The equilibrium constant for the reverse reaction is the inverse of the equilibrium constant for the forward reaction. This statement is: —
Always true.
16.
Which of the following is a Brønsted-Lowry acid? —
HSO4-
17.
Which of the following is NOT a characteristic of a strong electrolyte? —
Exists in equilibrium between molecular and ionic forms.
18.
For the reaction A(g) + B(g) <=> C(g), increasing the temperature will shift the equilibrium to the right if the forward reaction is: —
Endothermic
19.
Which ion is responsible for the basicity of a solution? —
OH- ion
20.
Which of the following is an example of an ionic equilibrium? —
AgCl(s) <=> Ag+(aq) + Cl-(aq)
21.
Which of the following reactions will have an equilibrium constant (Kp) that is independent of pressure? —
H2(g) + I2(g) <=> 2HI(g)
22.
Which of the following is a conjugate acid-base pair? —
NH3 and NH4+
23.
Which of the following is amphoteric in nature? —
H2O
24.
The equilibrium constant for the reaction PCl5(g) <=> PCl3(g) + Cl2(g) is Kc. If the volume of the container is doubled, the value of Kc will: —
Remain unchanged
25.
The degree of dissociation of a weak electrolyte increases with: —
Decrease in concentration.
26.
Le Chatelier's principle states that if a change of condition is applied to a system in equilibrium, the system will shift in a direction that... —
Counteracts the effect of the change.
27.
The presence of a catalyst affects the equilibrium by: —
Decreasing the time taken to reach equilibrium.
28.
Which of the following indicates a strong acid? —
Ka = 1.0 x 10^10
29.
The equilibrium constant Kp is related to Kc by the equation: —
Kp = Kc(RT)^(Δn)
30.
A solution is supersaturated if it contains: —
More solute than it can normally dissolve.
31.
The pH of a solution is defined as: —
-Log10[H+]
32.
Which salt will produce an acidic solution upon hydrolysis? —
NH4Cl
33.
Which of the following is a Lewis acid? —
BF3
34.
The relationship between pH and pOH in an aqueous solution at 25°C is: —
pH + pOH = 14
35.
The buffer capacity of a buffer solution is maximum when: —
pH = pKa
36.
The Henderson-Hasselbalch equation is used to calculate the pH of a buffer solution and is given by: —
pH = pKa + log([Base]/[Acid])
37.
For a reaction at equilibrium, the Gibbs free energy change (ΔG) is: —
Zero
38.
The solubility of AgCl will be lowest in which of the following solutions? —
0.01 M NaCl solution
39.
For a sparingly soluble salt M2X, if its molar solubility is 's', then its Ksp is given by: —
4s^3
40.
According to Le Chatelier's principle, adding an inert gas to a gaseous equilibrium at constant volume will: —
Not affect the equilibrium position.
41.
The addition of a catalyst to a system at equilibrium: —
Does not affect the equilibrium position but speeds up both forward and reverse reactions.
42.
A buffer solution resists changes in pH upon addition of small amounts of: —
Strong acid or strong base.
43.
In the Haber process for ammonia synthesis (N2(g) + 3H2(g) <=> 2NH3(g)), increasing the pressure will favor: —
The forward reaction (ammonia formation).
44.
The equilibrium constant expression for the reaction 2SO2(g) + O2(g) <=> 2SO3(g) is Kc = [SO3]^2 / ([SO2]^2 [O2]). This indicates: —
The reaction is reversible.
45.
Which of the following is a characteristic of a reversible reaction at equilibrium? —
The rate of the forward reaction is equal to the rate of the reverse reaction.
46.
If the ionic product of a solution is greater than its solubility product (Q > Ksp), then: —
Precipitation will occur.
47.
According to Ostwald's dilution law, for a weak electrolyte, the degree of dissociation (alpha) is proportional to: —
The inverse of the square root of concentration.
48.
A solution in which no more solute can be dissolved at a given temperature is called: —
Saturated
49.
In an aqueous solution of a weak acid, the concentration of undissociated acid molecules is: —
Greater than the concentration of ions.