Question

$50\, ml.$ of $H_{2}SO_{4}$ require $10\, gm\, CaCO_{3}$ for complete decomposition. The normality of acid is:

• A. 2
• B. 0.30
• C. 4
• D. 0.20

Answer 1

Answer: (C)

$\because 100\, gm\, CaCO _{3} =98\, gm\, H _{2} SO _{4}$
$\therefore 10\, gm\, CaCO _{3} =\frac{98 \times 10}{100}$
$=9.8\, gm$ of $H _{2} SO _{4}$
$\therefore 50\, ml$ of solution have $9.8\, gm$ of $H _{2} SO _{4}$
$\therefore 1000\, ml$ of solution have
$=\frac{9.8 \times 1000}{50}$
$=196\, gm$ of $H _{2} SO _{4}$
We know that
$N =\frac{W}{\text { equivalent weight }} \times \frac{1000}{V}$
$=\frac{196 \times 1000}{49 \times 1000}=4$
$\therefore N =4$