Question

Which statement is correct for pure water? A) Pure water contains equal amounts of hydroxide, [OH-], and hydronium, [H3O+], ions. B) Pure water contains larger amounts of hydroxide, [OH-], ions than hydronium, [H3O+], ions. C) Pure water contains larger amounts of hydronium, [H3O+], ions than hydroxide, [OH-], ions. D) Pure water is an electrolyte.

Answer 1

A)pure water contains equal amount of hydroxide and hydronium ion

Answer 2

Answer:

The correct answer is option A.

Explanation:

A pure water has pH value of 7 which neutral in nature. Pure water equal amount of hydronium ions and hydroxide ions.

$H_2O+H_2O\rightleftharpoons H_3O^++OH^-$

Ionic product of water = $K_w=1\times 10^{-14}$

$[H_3O^+]=[OH^-]$

$K_w=1\times 10^{-14}=[H_3O^+]\times [OH^-]$

$[H_3O^+]=10^{-7}$

The pH value of pure water :

$pH=-\log[H_3O^+]=-\log[10^{-7}] = 7$