Question

$60ml$ of $0.1MHCl$ is mixed with $40ml$ of $0.05M{H}_{2}S{O}_4$. The $pH$ value of the resulting solution is _______.

• A. $2$
• B. $0$
• C. $7$
• D. $1$

Answer 1

Answer: (D)

$1$

$60$ $mL$ of $0.1$ $M$ $HCl$

No. of moles $=$ Molarity $\times$ Volume (Litres)

Final Normality $=\frac{N_1{V}_1+N_2{V}_2}{V_1+V_2}=\frac{60\times 0.1+40\times 0.05\times 2}{100}$ ($\because H_{2}S{O}_4$ $n$ factor is $2$)

$=\frac{6+4}{100}=0.1$

$\left[H^{+}\right]=0.1$

$pH=-\log \left(0.1\right)=1$