Determine the empirical formula for a compound that is 70.79% carbon,8.91% hydrogen,4.59% nitrogen,and 15.72% oxygen. A) C₁₈H₂₇NO₃ B) C₁₈H₂₇NO₂ C) C₁₇H₂₇NO₃ D) C₁₇H₂₆NO₃

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Quizplus · Accepted Answer

To find the empirical formula, convert the percentages to moles: - Carbon: 70.79 g / 12.01 g/mol = 5.895 moles - Hydrogen: 8.91 g / 1.008 g/mol = 8.839 moles - Nitrogen: 4.59 g / 14.01 g/mol = 0.328 moles - Oxygen: 15.72 g / 16.00 g/mol = 0.983 moles Divide each by the smallest number of moles (0.328): - C: 5.895 / 0.328 ≈ 18 - H: 8.839 / 0.328 ≈ 27 - N: 0.328 / 0.328 = 1 - O: 0.983 / 0.328 ≈ 3 The empirical formula is C₁₈H₂₇NO₃.

Determine the Empirical Formula for a Compound That Is 70