Chemistry · Some Basic Concepts of Chemistry (Mole Concept) + Stoichiometry

JEE Main 2026 — 21 January, Morning Shift — Question 53

14.0 g14.0\,\mathrm{g} of calcium metal is allowed to react with excess HCl\mathrm{HCl} at 1.0 atm1.0\,\mathrm{atm} pressure and 273 K273\,\mathrm{K}. Which of the following statements is incorrect?

[Given: Molar mass in g mol−1\mathrm{g\,mol^{-1}} — Ca=40\mathrm{Ca}=40, Cl=35.5\mathrm{Cl}=35.5, H=1\mathrm{H}=1]

  1. Option A:

    0.35 mol0.35\,\mathrm{mol} of H2\mathrm{H_2} gas is evolved.

  2. Option B:

    7.84 L7.84\,\mathrm{L} of H2\mathrm{H_2} gas is evolved.

  3. Option C:

    33.3 g33.3\,\mathrm{g} of CaCl2\mathrm{CaCl_2} is produced.

    Correct
  4. Option D:

    The limiting reagent is calcium metal.

Answer: C

Step-by-step solution

Reaction: Ca+2HCl→CaCl2+H2\mathrm{Ca + 2HCl \rightarrow CaCl_2 + H_2}

Moles of calcium =14.040=0.35 mol=\frac{14.0}{40} = 0.35\,\mathrm{mol}

From stoichiometry, 1 mol Ca→1 mol H21\,\mathrm{mol\ Ca} \rightarrow 1\,\mathrm{mol\ H_2}

Hence, H2\mathrm{H_2} formed =0.35 mol= 0.35\,\mathrm{mol}

Volume of H2\mathrm{H_2} at 273 K273\,\mathrm{K} and 1 atm1\,\mathrm{atm}, V=0.35×22.4=7.84 LV = 0.35 \times 22.4 = 7.84\,\mathrm{L}

Molar mass of CaCl2\mathrm{CaCl_2} =40+2×35.5=111 g mol−1= 40 + 2 \times 35.5 = 111\,\mathrm{g\,mol^{-1}}

Mass of CaCl2\mathrm{CaCl_2} formed =0.35×111=38.85 g= 0.35 \times 111 = 38.85\,\mathrm{g}

Thus statement (C) is incorrect.

Since HCl\mathrm{HCl} is in excess, calcium is the limiting reagent.

Answer key and solution verified before publishing.

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Exam
JEE Main 2026
Subject
Chemistry
Chapter
Some Basic Concepts of Chemistry (Mole Concept) + Stoichiometry
Topic
Chemical Equations, Stoichiometry and Limiting Reagent
14.0\, g of calcium metal is allowed to react with excess HCl at… | JEE Main 2026 PYQ with Solution · DhiX AI