Physics I / Representations from particles to formulas
Practice question · True or false

The empirical formula of a compound always matches its molecular formula.

Hints
  1. Compare glucose with formaldehyde.
  2. Both are CH₂O in simplest ratio.
Show the answer

False

Why

False. The empirical formula gives the simplest whole-number ratio; the molecular formula gives the actual count. Glucose C6H12O6C_6H_{12}O_6 and formaldehyde CH2OCH_2O share the empirical formula CH2OCH_2O and are entirely different substances, which is why combustion analysis alone cannot identify a compound.

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