Question 1 Report
The relative molecular mass of an alkanoic acid with the empirical formula of CH\(_2\)O is
[ H = 1, C = 12, O = 16 ]
An alkanoic acid (carboxylic acid) has the general formula \(\text{C}_n\text{H}_{2n}\text{O}_2\). The task is to find the molecular formula whose empirical formula is CH\(_2\)O and whose molecular formula fits the alkanoic acid pattern.
First, calculate the empirical formula mass of CH\(_2\)O:
\[12 + 2(1) + 16 = 30\]
The molecular formula must be a whole-number multiple of the empirical formula: \((\text{CH}_2\text{O})_n\). To satisfy the alkanoic acid general formula \(\text{C}_n\text{H}_{2n}\text{O}_2\), we need 2 oxygen atoms, which requires \(n = 2\):
\[(\text{CH}_2\text{O})_2 = \text{C}_2\text{H}_4\text{O}_2\]
This is ethanoic acid (acetic acid, CH\(_3\)COOH), a well-known alkanoic acid.
The relative molecular mass is:
\[2(12) + 4(1) + 2(16) = 24 + 4 + 32 = 60\]
The answer is 60.
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