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Question 600017
JEE Chemistry · Medium

Mole Concept and Stoichiometry: Law of Conservation of Mass MCQ

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Law of Conservation of MassMediumQuestion 600017

Question

In the reaction 2H₂ + O₂ → 2H₂O, if 4 g of H₂ reacts with 32 g of O₂, the mass of water produced is:
  1. A
    28 g
  2. B
    36 g
    Correct
  3. C
    32 g
  4. D
    18 g

Correct answer

36 g

Explanation

By conservation of mass: 4 + 32 = 36 g. All reactants are used up (H₂: 4/2 = 2 mol; O₂: 32/32 = 1 mol; ratio 2:1 ✓). Water = 36 g.

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