Question

If the pH of an aqueous solution of NaOH is 11,then concentration of hydroxide ions in mol/L will be?

Answer 1

Answer : The concentration Hydroxide ions will be 0.001 moles/L

Solution : Given,

$pH=11$

As we know that,  $pH+pOH=14$

Now put the value of pH in above expression, we get the value of pOH.

11 + pOH = 14

pOH = 14 - 11

pOH = 3

Now we have to calculate the concentration of Hydroxide ion.

$pOH=-log[OH^-]$

$3=-log[OH^-]$

So, $[OH^-]=10^{-3}=0.001moles/L$

Therefore, the concentration Hydroxide ions will be 0.001 moles/L