The unit of the ionic product of water $K_w$ is:

The $[H^{+}]$ in lemon juice is found to be $0.0063 \ M$. What is the $pH$ value of lemon juice? $(\log 6.3 = 0.7993)$

There are two different solutions, $A$ and $B$. The $pH$ of solution $A$ is $4$. Find the $pH$ of solution $B$ having $[H^+]$ concentration three times that of solution $A$.

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

$pH + pOH$ is equal to

The $pH$ of blood is .....