Question Detail
Question
If a compound has a molar mass of 100 g/mol and contains 25 g of element A, what is the % composition of A?
Correct Answer
Option B is the correct answer.
Detailed Explanation
Percentage composition of A = (mass of A in one mole / molar mass of compound) × 100 = (25 g / 100 g) × 100 = 25%.
Hint
Divide the mass of the element by the total molar mass and multiply by 100.