Chemistry

Question Analysis
This question assesses the student's ability to determine the empirical formula from the percent composition of a compound.

Key Concept Explanation
To find the empirical formula, convert the percent composition to grams, then to moles, and finally find the simplest whole-number ratio of moles.

Step-by-step Solution
1. Assume a 100 g sample: C: 40.0 g, H: 6.7 g, O: 53.3 g.
2. Convert grams to moles: C: 40.0 g / 12.01 g/mol ≈ 3.33 mol, H: 6.7 g / 1.008 g/mol ≈ 6.65 mol, O: 53.3 g / 16.00 g/mol ≈ 3.33 mol.
3. Find mole ratio (divi...