Multiple Choice Questions
1. Which of the following is incorrect?
a) K acd K arepnot usually equal.
b) A large equilibrium constant (K >10 ) cndicates that products are favored in equilibrium.
c) The addition of a catalyst does not shift the equilibrium in either way.
d) In equilibrium, forward and reserved reactions have the same rate constants.
e) The equilibrium constant is temperature dependent.
2. Which of the following cannot be the units of the rate constant
d) M /s
e) M /s
3. A certain reaction has an activation energy of 83 kJ/mol. If the rate constant of this reaction is
2.1x10 s at 150 °C, what is the rate constant at 300°C?
a) 1 s
b) 10 s -1
c) 0.02 s
d) 6.3 s -1
e) 9.7 s -1
4. The following reactions involving bromine and chlorine all occur in water
1. BrCl + H O 2 HOBr + Cl + H - + K1= 1.8 x 10 -5
- - 4
2. BrCl + Br Br Cl 2 K 2 1.8 x 10
3. Br Cl Br + Cl - K = 1.3
2 2 3
What is the equilibrium constant for the net reaction Br + H O 2OBr +2Br + H in the - +
presence of chloride, and would you expect the equilibrium to favour products or reactants?
a) K = 7.7 x 10 , favouring reactants
b) K = 7.7 x 10 , favouring products
c) K = 3.8 x 10 , favouring reactants
d) K = 1.9 x 10 , favouring reactants
e) K = 1.9 x 10 , favouring products 5. The equilibrium constant K for phe reaction below is 2x10 -42at 25°C
2H 2 (g) 2H (g)2+ O (g)2
What is K fcr the reaction at the same temperature?
a) 8 x 10 -46
b) 8 x 10
c) 8 x 10
d) 5 x 10 -39
e) 3 x 10
6. A mixture of 5.75 atm of H and25.75 atm of I is pl2ced in a 1.0L vessel at 430°C. The equilibrium
constant for the reaction : H 2g) + I2(g) 2HI (g)
At this temperature is K =P54.3. What is the partial pressure of HI, in equilibrium?
a) 4.52 atm
b) 9.04 atm
c) 1.23 atm
d) 5.75 atm
e) 42.37 atm
7. Which of the following can be shown to be both a Brønsted acid and a Brønsted base?
a) No 3-
b) PO 4
d) HCO 3
e) CIO 4
8. The value of K foW water at body temperature (37°C) is 2.1 x 10 . Calculate the pH.
9. A 100 ml sample of 0.1 M CH NH K 3 3.2 b 10 is titrated with 0.25 M HNO . Calculate3the pH
after addition of 40ml.
e) 7.00 10. A titration was followed using a pH electrode, revealing that the pH at the equivalence point
was 5.29. This suggests that the titration involved:
a) A strong acid and a strong base
b) A strong acid and a weak base
c) A weak acid and a weak base
d) A strong base and a we