Question

$100mL$ each of $0.4NNaOH$, $0.2NHCl$ and $0.1N{H}_{2}S{O}_4$ are mixed together. The resulting solution will be:

• A. Acidic, $0.02N$
• B. Basic, $0.03N$
• C. Neutral, $0.01N$
• D. Basic, $0.02N$

Answer 1

The correct option is B Basic, $0.03N$

Milliequivalents of $H_{2}S{O}_4$ = $Volume\left(mL\right)\times Normality=100\times \frac{1}{10}=10$

Milliequivalents of $HCl$ = $Volume\left(mL\right)\times Normality=100\times \frac{1}{5}=20$

Milliequivalents of $NaOH$ = $Volume\left(mL\right)\times Normality=100\times 0.4=40$

So, Milliequivalents of $H^{+}$ = $\text{Milliequivalents of}{H}_{2}S{O}_4+HCl=30$

Milliequivalents of acid and base react in $1:1$ ratio

So, milliequivalents of base left = $40-30$ = $10$

Thus, normality of excess base left = $\frac{10\left(meq\right)}{300\left(ml\right)}=0.03N$

Since, base is left the solution is basic or alkaline.