Question

If 40 g $CaCO_{3}$ is treated with 40 g HCl. Which of the reactants will act as limiting reagent?

• A. $CaCO_{3}$
• B. HCl
• C. Both are equal
• D. Cannot be calculated.

Answer 1

Answer: (A)

$CaCO_{3}$

Answer 2

(1) : $\underset{\begin{aligned} & 1mole \\ & (100g) \end{aligned}}{CaCO_{3}} + \underset{\begin{aligned} & 2moles \\ & (73g) \end{aligned}}{2HCl} \rightarrow CaCl_{2} + H_{2}O + CO_{2}$

100 g of $CaCO_{3}$reacts with $73g$of HCl

40 g of $CaCO_{3}$will react with

$\frac{73}{100} \times 40 = 29.2g$of HCl since $CaCO_{3}$is

completely consumed and some amount $(40 - 29.2 = 10.8g)$ of HCl remains unreacted and hence, $CaCO_{}$is limiting reagent.