Question

Based on a Kc value of 0.200 and the data table given, what are the equilibrium concentrations of XY , X , and Y , respectively?

Express the molar concentrations numerically.

Consider mixture C, which will cause the net reaction to proceed in reverse.

Concentration (M)initial:change:equilibrium:[XY]0.200+x0.200+x←net⇌[X]0.300−x0.300−x+[Y]0.300−x0.300−x

The change in concentration, x , is positive for the reactants because they are produced and negative for the products because they are consumed.

Answer 1

XY    <-------------------------> X      +    Y

0.2 + x                        0.3-x      0.3 - x

Kc = [X][Y]/[XY]

0.200 = (0.3-x)^2 / 0.2 + x

0.04 + 0.2 x = 0.09 + x^2 - 0.6 x

x^2   - 0.8 x + 0.05 = 0

x   = 0.732 or x = 0.0683

equilibrium concentrations :

[XY] = 0.268 M

[X] = 0.232 M

[Y] = 0.232 M