At a given temperature , equilibrium is attained when 50% of each reactant is converted into products.?

Question

A(g)+B(g)----> C(g) +D(g) ; if amount (in mol) of B(g) is doubled , % of B converted into products will be: Ans..33.33%

Answer 1

K = [C][D]/[A][B]

From first fact given, equilibrium is attained when A, B,C,D are equal,so K = 1.

Now set up a Reaction/Initial/change/equilibrium table:

Initially, A = x, B = 2x, C = 0, D = 0

Let the amount of B that reacts be Y. Then change in A and B is -Y; in C and D is+Y.

Finally, then, A = x - Y; B = 2x - Y; C = Y, D = Y

K = [Y][Y]/[x - Y][2x - Y]; but K = 1; so Y^2 = 2 x^2 - 3xY + Y^2,

2x^2 = 3xY

Y/x = 2/3 = 1/3 x initial [B]

:-)