Concept:The molecular formula is a simple whole-number multiple of the empirical formula. The multiplier (n) is found by dividing the molecular mass by the empirical formula mass.
Formula:$$ n = \frac{\text{Molar Mass}}{\text{Empirical Formula Mass}} $$
Solution:- First, calculate the Empirical Formula Mass of \( \text{C}_3\text{H}_3\text{O} \):
- \( (3 \times 12) + (3 \times 1) + (1 \times 16) = 36 + 3 + 16 = 55 \text{ g/mol} \).
- Given Molar Mass = \( 110.15 \approx 110 \text{ g/mol} \).
- Calculate multiplier \( n = 110 / 55 = 2 \).
- Molecular formula = \( 2 \times (\text{C}_3\text{H}_3\text{O}) = \text{C}_6\text{H}_6\text{O}_2 \).
Why other options are incorrect:- Option B: Does not match the required \( n=2 \) multiplier.
- Option C: Does not share the same empirical formula ratio.
- Option D: Corresponds to an incorrect multiplication where oxygen was tripled instead of doubled.
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