Question Detail
Question
What is the mass percent composition of bromine in haloethane (C₂HBrClF)?
Correct Answer
Option B is the correct answer.
Detailed Explanation
Molar mass of C₂HBrClF = (2×12.01) + 1.01 + 79.90 + 35.45 + 19.00 = 24.02 + 1.01 + 79.90 + 35.45 + 19.00 = 159.38 g/mol. Mass percent of Br = (79.90 / 159.38) × 100% = 50.13%. There appears to be a discrepancy with the provided answer key (40.51%). The calculation for C₂HBrClF yields ~50.1%, suggesting a possible different compound or error in the question stem as given.
Hint
Mass percent = (mass of element in one mole / molar mass of compound) × 100%.