The Conductivity of a Solution of Methanoic Acid, HCOOH, Which

The conductivity of a solution of methanoic acid, HCOOH, which was made by dissolving 0.921 g of acid in water and making up the volume to 1.00 dm³, was measured to be 5.05 × 10^-4 S m^-1 at a temperature of 298 K. Determine the acid dissociation constant of methanoic acid at this temperature.

A) 0.234
B) 1.82
C) 0.550
D) 0.192