Question

$200\text{mL}$ of $0.1\text{M}$ $H_{2}S{O}_4$ is added to $300\text{mL}$ of $0.1\text{M}$ $NaOH$ solution. Find the normality of the ions in excess ($H^{+}$ or $O{H}^{-}$) in the resultant solution.

• A. $0.25\text{N}$
• B. $0.30\text{N}$
• C. $0.02\text{N}$
• D. $0.05\text{N}$

Answer 1

The correct option is C $0.02\text{N}$

Milliequivalents of $NaOH$ $=300\times 0.1\times 1=30mEq$
Milliequivalents of $H_{2}S{O}_4=200\times 2\times 0.1=40mEq$
Since, the acid is present in excess, the solution is acidic.
Hence, milliequivalents of excess $H^{+}$ $=40–30=10mEq$
Normality of $H^{+}=\frac{10}{500}=0.02\text{N}$.