Problem

At a definite temperature, the equilibrium constant for a reaction,

A + B \rightleftharpoons 2C

, was found to be 81. Starting with 1 mole

A

and 1 mole of

B

, the mole fraction of

C

at equilibrium is : a.

\frac{9}{11}

\frac{1}{11}

\frac{2}{11}

\frac{7}{11}