A. formic acid is a weak acid found in insect stings. it partially dissoc hcho2 cho2 + h '. the equilibrium constant describing the dissociation is k-points) ates in water according to the reaction (6 i) if a solution of formic acid contains 0.2 m hcho2, 0.006 m cho2, and 0.006 mh ', what is the k, of the acid ?

Answer is: K for the formic acid is 1.8·10⁻⁴ M.

Chemical dissociation of formic acid in the water:
HCOOH(aq) ⇄ HCOO⁻(aq) + H⁺(aq).
K = [HCOO⁻] · [H⁺] / [HCOOH].
[HCOOH] = 0.2 M; equilibrium concentration of formic acid.
[H⁺] = 0.0.6 M, equilibrium concentration of hydrogen cations.
[HCOO⁻] = 0.006 M; equilibrium concentration of formate.
K = (0.006 M)² / 0.2 M.
K = 0.00018 M.
K = 1.8·10⁻⁴ M.