The concentration of hydrogen ions in a given solution is $6 \times 10^{-4} \ M$. The $pH$ of the solution is:

The unit of the ionic product of water $(K_W)$ is.......

The ionic product of water increases with which of the following changes?

$2$. Given below are two statements:
Statement $I$: The changes in $pH$ with temperature are so small that we often ignore them.
Statement $II$: When the hydrogen ion concentration changes by a factor of $100$,the $pH$ changes by one unit.
In the light of the above statements,identify the correct answer from the options given below:

What is the concentration of $OH^{-}$ ion in a solution containing $0.05 \ M \ H^{+}$ ions?

The $[OH^{-}]$ in a solution is $1 \times 10^{-12} \ mol \ dm^{-3}$. What is the concentration of $H^{+}$ ions?