If $1 \ mL$ of $1 \ M \ HCl$ solution is added to $99 \ mL$ of aqueous solution of $NaCl$,the $pH$ of the solution changes by $X$ units. The value of $X$ is:

What is the normality of an aqueous solution of $H_2SO_4$ having $pH = 1$ (in $N$)?

Calculate the $pH$ of $0.0035 \ M \ Ba(OH)_2$ solution.

Given the concentrations of different acids in the following mixtures,which mixture has the highest $pH$?

When $50 \, mL$ of $0.4 \, N$ $HCl$ and $50 \, mL$ of $0.2 \, N$ $NaOH$ solutions are mixed,the $pH$ of the resulting solution will be ........

Given below are two statements:
Statement-$I$: $pH$ of a $1.0 \times 10^{-8} \ M$ solution of $HCl$ is $8$ at $25^{\circ} C$.
Statement-$II$: $HCl$ is a strong acid and negative log of $H^{+}$ concentration is called $pH$.
In the light of the above statements,choose the most appropriate answer from the options given below: