Question

3. The concentration of H+ ions in 0.1 M solution of a weak acid is 1.0 x 10mol L''. Calculate the
dissociation constant of the acid​

Answer 1

HA⇌H + +A −

Initial concentration 0.1 0 0

Equilbrium concentration 0.1−1×10 −5 1×10 −51×10−5

[HA] can be taken as 0.1 M as 1×10 −5 is very small.

K a = [HA][H + ][A − ] = 0.11×10 −5 ×1×10 −5

=10 −9