What is the empirical formula of a compound con... - JAMB Chemistry 2023 Question

To determine the empirical formula, we need to find the simplest whole-number ratio of the atoms in the compound.

Let's assume we have 100 grams of the compound to make percentage to mass conversions easier.

- Carbon: \(40.00\% \rightarrow 40.00 \, \text{g}\)
- Hydrogen: \(6.67\% \rightarrow 6.67 \, \text{g}\)
- Oxygen: \(53.33\% \rightarrow 53.33 \, \text{g}\)

Next, we need to find the mole ratios by dividing each mass by the molar mass of the respective element.

- Moles of Carbon: \(\frac{40.00 \, \text{g}}{12.01 \, \text{g/mol}} \approx 3.33\)
- Moles of Hydrogen: \(\frac{6.67 \, \text{g}}{1.01 \, \text{g/mol}} \approx 6.60\)
- Moles of Oxygen: \(\frac{53.33 \, \text{g}}{16.00 \, \text{g/mol}} \approx 3.33\)

Now, we find the simplest whole-number ratio by dividing each mole value by the smallest of the three:

- Carbon: \(\frac{3.33}{3.33} \approx 1\)
- Hydrogen: \(\frac{6.60}{3.33} \approx 2\)
- Oxygen: \(\frac{3.33}{3.33} \approx 1\)

The ratio is \(1:2:1\), suggesting the empirical formula is \(CH_2O\).

Therefore, the correct answer is: CH₂O