Question

To determine equilibrium concentrations from initial conditions.

The reversible reaction

XY(aq)⇌X(aq)+Y(aq)

has a reaction quotient Qc defined as

Qc=[X][Y][XY]

Because the reaction is reversible, both the forward and reverse reactions will occur simultaneously. The reaction will eventually reach equilibrium, at which point the concentrations do not change, and Qc is equal to a constant known as Kc.

Consider mixture B, which will cause the net reaction to proceed forward.

Concentration (M)initial:change:equilibrium:[XY]0.500−x0.500−xnet→⇌[X]0.100+x0.100+x+[Y]0.100+x0.100+x

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

a.)Based on a Kc value of 0.220 and the given data table, what are the equilibrium concentrations of XY, X, and Y, respectively?

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.

b.)Based on a Kc value of 0.220 and the data table given, what are the equilibrium concentrations of XY, X, and Y, respectively?