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Question 600057
JEE Chemistry · Hard

Mole Concept and Stoichiometry: Percentage Composition MCQ

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Percentage CompositionHardQuestion 600057

Question

A compound of X and O has 40% X. Molar mass = 80 g/mol. How many O atoms per formula unit?
  1. A
    1
  2. B
    2
  3. C
    3
    Correct
  4. D
    4

Correct answer

3

Explanation

%O = 60%. Mass of O in 1 mol = 0.6 × 80 = 48 g. Number of O atoms = 48/16 = 3.

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