Q54Multiple choice
Write a relation between ∆G and Q and define the meaning of each term and answer the following :
- (a)Why a reaction proceeds forward when Q < K and no net reaction occurs when Q = K.
- (b)Explain the effect of increase in pressure in terms of reaction quotient Q. for the reaction : CO (g) + 3H2 (g) CH4 (g) + H2O (g)
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∆G = ∆G + RT lnQ ∆G = Change in free energy as the reaction proceeds ∆G = Standard free energy change Q = Reaction quotient R = Gas constant T = Absolute temperature Since ∆G = – RT lnK ∴ ∆G = – RT lnK + RT lnQ = RT ln K If Q < K, ∆G will be negative. Reaction proceeds in the forward direction. If Q = K, ∆G = 0, no net reaction. [Hint: Next relate Q with concentration of CO, H2, CH4 and H2O in view of reduced volume (increased pressure). Show that Q < K and hence the reaction proceeds in forward direction.] 103 Equilibrium