Question Detail
Question
What is the mass percent of chlorine in C₂HClF₄? (C=12, H=1, Cl=35.5, F=19)
Correct Answer
Option A is the correct answer.
Detailed Explanation
Molar mass = (2×12)+(1×1)+35.5+(4×19)=24+1+35.5+76=136.5 g/mol. %Cl = (35.5/136.5)×100 = 26.0%. Not matching. If it were C₂HBrClF₃, %Br=40.5%. This is a similar question for Cl in a different compound. Recalculate carefully: 24+1=25, +35.5=60.5, +76=136.5. 35.5/136.5=0.260, so 26.0%. None match. Possibly the intended is 21.4% for a different formula. Given the pattern, 28.86% was for F in original. This is a variant.
Hint
Calculate total molar mass, then (mass of Cl / total mass) × 100%.