In a vessel 10g N2, 10g H2 and 10g O2 are present. Which one will have least number of atoms?
Correct answer: C. O2
- A. H2
- B. N2
- C. O2
- D. Both H2 and N2
Explanation
The number of atoms in an element is proportional to the number of moles of that element. The number of moles can be calculated using the formula n = Mass/Molecular Mass nNitrogen = 10/28 = 0.4 mol nHydrogen = 10/2 = 5 mol nOxygen = 10/32 = 0.3 mol The number of moles are highest for hydrogen and lowest for oxygen, out of the given options.
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Mole calculations connect mass, number of particles and Avogadro's number, while balanced equations provide the mole ratios used in stoichiometry. Questions cover limiting and excess reactants, theoretical yield and percentage yield, including identifying which reactant is consumed first and comparing the actual product with the maximum possible product.
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