Concept:The molecular formula is determined by finding the multiplier integer (n) which links the empirical formula mass to the total molecular mass.
Formula:$$ n = \frac{\text{Molecular Mass}}{\text{Empirical Formula Mass}} $$
Solution:- Calculate the Empirical Formula Mass of \( \text{CH}_2\text{O} \):
- C(12) + 2H(2) + O(16) = \( 12 + 2 + 16 = 30 \text{ g/mol} \).
- The total given Molecular Mass is 60.
- Calculate multiplier \( n \): \( 60 / 30 = 2 \).
- Multiply every subscript in the empirical formula by 2: \( 2 \times (\text{CH}_2\text{O}) \).
- The resulting molecular formula is \( \text{C}_2\text{H}_4\text{O}_2 \). (This is acetic acid).
Why other options are incorrect:- \( \text{C}_2\text{H}_6\text{O}_2 \): Doesn't maintain the 1:2:1 empirical ratio (Hydrogen is too high).
- \( \text{C}_6\text{H}_{11}\text{O}_4 \) & \( \text{C}_3\text{H}_4\text{O}_2 \): These have entirely mismatched molar masses that do not equal 60.
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