Engineering Board Exam Reviewer · Chemistry · hard

A hydrocarbon contains 85.7% carbon and 14.3% hydrogen by mass. What is its empirical formula? (Use H = 1, C = 12, N = 14, O = 16, Na = 23, S = 32, Cl = 35.5, Ca = 40)

  1. CH
  2. CH3
  3. CH2
  4. CH4

Answer

C. CH2

Solution

C: 85.7/12 = 7.14; H: 14.3/1 = 14.3. Ratio 1 : 2 CH2.

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