Element A (atomic weight 12.01) and element B (atomic weight 16) combine to form a new substance X. If two moles of B combine with one mole of A, then the weight of one mole of X is:
Correct answer: C. 44.01 g
- A. 28.01 g
- B. 40.02 g
- C. 44.01 g
- D. 56.02 g
Explanation
The problem states the formula of substance X is AB₂. The molar mass of X is the sum of the masses of its components: (1 × 12.01) + (2 × 16) = 12.01 + 32 = 44.01 g/mol
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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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