Equilibrium · Question 59

A buffer solution is prepared in which the concentration of NH3 is 0.30 M and the concentration of NH4+ is 0.20 M. If the equilibrium constant, Kb for NH3 equals 1.8 10-5, what is the pH of this solution? ( 2.7 = 0.43)

1. 9.08
2. 9.43
3. 11.72
4. 8.73

Which of the following is least likely to behave as Lewis base?

1. H2O
2. NH3
3. BF3
4. OH-

For the reaction, N2(g) + O2(g) 2NO(g), the equilibrium constant is K1. The equilibrium constant is K2 for the reaction, 2NO(g) + O2(g) 2NO2(g) What is K for the reaction, NO2(g) 12N2(g) + O2(g)

1. 12K1K2
2. 14K1K2
3. [ 1K1K2 ]1/2
4. 1K1K2

The reaction, 2A(g) + B(g) 3C(g) + D(g) is begun with the concentrations of A and B both at an initial value of 1.00 M. When equilibrium is reached, the concentration of D is measured and found to be 0.25 M. The value for the equilibrium constant for this reaction is given by the expression

1. [(0.75)3(0.25)] [(1.00)2(1.00)]
2. [(0.75)3(0.25)] [(0.50)2(0.75)]
3. [(0.75)3(0.25)] [(0.50)2(0.25)]
4. [(0.75)3(0.25)] [(0.75)2(0.25)]

If pH of a saturated solution of Ba(OH)2 is 12, the value of its Ksp is

1. 4.00 10-6 M3
2. 4.00 10-7 M3
3. 5.00 10-6 M3
4. 5.00 10-7 M3

What is [H+] in mol/L of a solution that is 0.20 M in CH3COONa and 0.10 M in CH3COOH? Ka for CH3COOH = 1.8 10-5

1. 3.5 10-4
2. 1.1 10-5
3. 1.8 10-5
4. 9.0 10-6

In which of the following equilibrium Kc and Kp are not equal?

1. 2NO(g) N2(g) + O2(g)
2. SO2(g) + NO2(g) SO3(g) + NO(g)
3. H2(g) + I2(g) 2HI(g)
4. 2C(s) + O2(g) 2CO(g)

In a buffer solution containing equal concentration of B- and HB, the Kb for B- is 10-10. The pH of buffer solution is

1. 10
2. 7
3. 6
4. 4

The dissociation constants for acetic acid and HCN at 25 are 1.5 10-5 and 4.5 10-10 respectively. The equilibrium constant for the equilibrium CN- + CH3COOH HCN + CH3COO- would be

1. 3.3 10-5
2. 3.3 10-4
3. 3.3 104
4. 3.3 105

Which of the following molecules acts as a Lewis acid?

1. (CH3)2O
2. (CH3)3P
3. (CH3)3N
4. (CH3)3B