Question

For all of the problems below, here is the reaction: A <=> B. Assume in each case that the temperature is 300 K. (6.) If the Delta G for the reaction is 8 kJ/mol when there is 0.5M A and 0.2M B, what is the equilibrium concentration of A

Answer 1

delG = -RT lnK

8*1000=- 8.314* 300* lnK

lnK= -3.21

K= exp(-3.21) =0.04046

for the reaction is A-àB

K= [B]/[A]

Initial

A   0.5 M         and B   0.2M

Let x is the dissociation

At Equilibrium

A 0.5-x    and B 0.2+x

K=( 0.2+x)/(0.5-x)= 0.04046

0.2+x= 0.04046*(0.5-x)

0.2+x= 0.04046*0.5-0.04046x

Therefore x*(1+0.04046)= 0.04046*0.5-0.2

x is giving becoming –ve. The reaction does not proceed in the forward direction.