A solution is made by mixing 30.0 mL of 0.150M (mol/L) compound A with 25.0 mL of 0.200M (mol/L) compound B. At equilibrium, the concentration of C is 0.0454M. Calculate the equilibrium constant, K, for this reaction.

Keq = 6.105

Explanation:

A + B → C

∴ Keq = [ C ] / ([ A ] * [ B ])

∴ [ C ] = 0.0454 M

⇒ [ A ] = ((0.030 L) (0.150 M)) / (0.03 + 0.025) = 0.0818 M

⇒ [ B ] = ((0.025 L) (0.200)) / (0.03 + 0.025) = 0.0909 M

⇒ Keq = (0.0454) / ((0.0818) (0.0909))

⇒ Keq = 6.105