Question

One litre of solution contains 10–5 moles of H+ ions at 25⁰C. Percentage ionisation of water in solution is :

• A. 1.8 × 10–7 %
• B. 1.8 × 10–9 %
• C. 3.6 × 10–9 %
• D. 1.8 × 10–11 %.

Answer 1

Answer: (B)

1.8 × 10–9 %

Answer 2

In this solution, source of OH– is water

\ C$\alpha$= [OH–]

a = $\frac { 10 ^ { - 9 } } { 1000 / 18 }$= 1.8 × 10–11 M

% ionisation = 1.8 × 10–9 M