1. The equilibrium constant of the balance reaction below is 1.6 x 10-2 at 25 oC and 2.7 x 10-5 at 125 oC.

AB (g) + C (g)  3D (g) Which of the following is wrong for this reaction?

a) Adding catalyst does not change the equilibrium constant of the reaction.
b) The reaction is exothermic.
c) If the total pressure is increased, the partial pressure of the product increases
d) Increasing the concentration of C gas in the environment increases the concentration of D gas.
e) Increasing the volume affects balance

2. Which of the following reduces the occurrence of HI in the given reaction?
H2 (g) + I2 (g) 2HI (g) ΔH = 52.96 kJ

a) Increasing the amount of H2 b) Removing HI from the environment c) Lowering the temperature
d) Halving the volume of the reaction vessel e) Increasing the amount of I2

1 answer

1. a is correct.
b. You will need to work this out. The van't Hoff equation is
ln(k2/k2) = delta Ho(1/T1-1/T2)/R. Plug in the numbers and solve for delta Ho.
c is wrong. When P is increased the reaction will shift to the side with the smaller number of mols.
d is correct.
I don't know what you mean by answer e.

2. I assume you mean by "reduces the occurence of HI" causes the reaction to shift to the left. c is the correct answer but you should understand why this is correct and the others answers are not.