Question

The mass of $CaCO_3$ that completely reacts with 1 $dm^3$ of IN hydrochloric acid is

• A. 100 g
• B. 50 g
• C. 25 g
• D. 10 g

Answer 1

Answer: (B)

50 g

Answer 2

${CaCO_3 + 2HCl -> CaCl_2 + H_2O + CO_2}$
1 N = 1 M for HCI
Molarity = $\frac{w}{Mol.wt \times Volume}$
$1 = \frac{w}{36.5 \times 1}$
w = 36.5 g
$2 \times 36.5$ g of HCI combines with 100 g of $CaCO_3$
36.5 g of HCl combines with
$\frac{100 \times 36.5 }{2 \times 36.5 } g$ of $CaCO_3 = 50 \, g$ of $CaCO_3$.