If $pH$ of $A$,$B$,$C$ and $D$ are $9.5$,$2.5$,$3.5$ and $5.5$ respectively,then the strongest acid is

pH of $10^{-8} \ M \ HCl$ solution is

Calculate the $pH$ of the following solutions:
$(a)$ $2 \,g$ of $TlOH$ dissolved in water to give $2 \,L$ of solution.
$(b)$ $0.3 \,g$ of $Ca(OH)_2$ dissolved in water to give $500 \,mL$ of solution.
$(c)$ $0.3 \,g$ of $NaOH$ dissolved in water to give $200 \,mL$ of solution.
$(d)$ $1 \,mL$ of $13.6 \,M \,HCl$ is diluted with water to give $1 \,L$ of solution.

Five solutions of $KOH$ are prepared as follows: $1st \to 0.1 \ mol$ in $1 \ L$,$2nd \to 0.2 \ mol$ in $2 \ L$,$3rd \to 0.3 \ mol$ in $3 \ L$,$4th \to 0.4 \ mol$ in $4 \ L$,$5th \to 0.5 \ mol$ in $5 \ L$. What is the $pH$ of the resulting mixture?

Select the correct option that has the same $pH$ value.
$(1) 0.005 \, M \, H_2SO_4$
$(2) 0.1 \, M \, Na_2SO_4$
$(3) 10^{-2} \, M \, NaOH$
$(4) 0.01 \, M \, HCl$

The highest $pH$ $(14)$ will be of which of the following?