Question

a monobasic weak acid solution which is 0.002 M has ph value equal to 5 the percentage ionisation value of the acid in the solution will be​

Answer 1

A monobasic acid solution has pH value of 5. Its molarity is 0.005 M. The degree of ionisation of the acid is

Answer 2

The percentage ionisation value of the acid in the solution will be​ 0.5%

Let the degree of ionisation be α.

If the concentration of the solution is considered to be 'c' then,

α = [H⁺]/c

where, [H⁺] is the concentration of H⁺ ions in the solution.

Given, pH =5.

We know that, pH is the negative logartithm of the conc. of H⁺ ions.

So, [H⁺] = 10⁻⁵ M,

c = 0.002M

Replacing the values, we get,

α = (10⁻⁵ )/0.002

= 0.005

Expressing it as a percentage, we get

(0.005*100)%

= 0.5%