Question

0.001 mol of strong electrolyte m(oh)2 has been dissolved to make a 20ml of its saturated solution.its pH will be

Answer 1

Answer:- pH is 13.

Solution:- 0.001 mol of strong electrolyte $M(OH)_2$ are dissolved in water to make 20 mL of the saturated solution.

20 mL = 0.02 L

molarity of the solution = $\frac{0.001mol}{0.02L}$

molarity of the solution = 0.05 M

The given compound is a strong base and gives hydroxide ions in the aqueous solution as:

$M(OH)_2(aq)\rightarrow M^+^2(aq)+2OH^-(aq)$

1 mol of the compound gives two moles of hydroxide ions. So, the mol ratio is 1:2. The concentrations would also be in the same ratio.

The concentration of $[OH^-]$ = 2 x 0.05 M = 0.1 M

$pOH=-log[OH^-]$

pOH=-log(0.1)[/tex]

pOH = 1

pH + pOH = 14

pH = 14 - pOH

So, pH = 14 - 1

pH = 13

Hence, the pH of the given solution is 13.

Answer 2

hope it will help you