Question

Assume that product of water is $12$ at ${50}^{o}C$. Some statements related to the given statement are listed below:
$\left(a\right)$ Addition of an acid at the given temperature to water increases the ionic product of water because of increase in $H^{+}$ ions.
$\left(b\right)$ Addition of base to water decreases the ratio of $H^{+}$ to ${OH}^{-}$.
$\left(c\right)$ Addition of an acid on a base suppresses the dissociation of water molecules.
$\left(d\right)$ Ionic product of water varies only with temperature.
Which of the following option is correct?

• A. $a,b$ and $c$
• B. $b,c$ and $d$
• C. $c$ and $d$
• D. $a$ and $b$

Answer 1

The correct option is B $b,c$ and $d$

Water molecules can function as both acids and bases. Like any other equilibrium constant, the value of Ionic product $K_w$ varies with temperature. The formation of hydrogen ions and hydroxide ions from water is an endothermic process. According to Le Chatelier, if you increase the temperature of the water, the equilibrium will move to lower the temperature again. It will do that by absorbing the extra heat. On addition of acid the reaction equilibrium is displaced in order to counteract the change in the concentration of ion hydronium, i.e. the reaction is displaced to the left. Addition of base to water decreases the ratio of $H^{+}$ to $O{H}^{-}$.and addition of an acid on a base suppresses the dissociation of water molecules.