What is the empirical formula of a hydrocarbon that contains 85.7% carbon and 14.3% hydrogen by mass?
Answer and explanation
Correct answer: B. CH₂
- Step 1: Determine moles in a 100 g sample: C: ; H: .
- Step 2: Calculate the ratio: H/C . The simplest integer ratio is CH₂.
Answer
CH₂.
Why not the others: CH₃ requires 80% C and 20% H; C₂H₅ requires 82.8% C; CH requires 92.3% C (ethyne/benzene).
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