1 Potassium chlorate decomposes to product potassium chloride and oxygen gas. 2KClO3(s) ⇔ 2KCl(s) + 3O2(g) When this reaction was run at room temperature, the following equilbrium concentrations were measured: [O2] = 0.0500 M; [KCl] = 0.00250 M; [KClO3] = 2.00 M What is the equilibrium constant for this reaction?

Equilibrium constant is the ratio of the concentration of products to the concentration of reactants each term raised to its stochiometric coefficients.

The given balanced equilibrium reaction is,

[tex]2KClO_3(s)\rightleftharpoons 2KCl(s)+3O_2(g)[/tex]

At eqm. conc. (2.00) M ( 0.00250 ) M (0.0500) M

The expression for equilibrium constant for this reaction will be,

[tex]K_c=\frac{[KCl]^2\times [O_2]^3}{[KClO_3]^2}[/tex]

Now put all the given values in this expression, we get :

[tex]K_c=\frac{(0.00250)^2\times (0.0500)^3}{(2.00)^2}[/tex]

By solving we get :

[tex]K_c=1.95\times 10^{-10}[/tex]

Thus the equilibrium constant for this reaction is [tex]1.95\times 10^{-10}[/tex]