Final answer:
To find the empirical formula for ninhydrin, we need to know the composition of all elements, including nitrogen, which seems to be missing from the given data. The provided percentages for C, H, and O do not allow a complete determination of the correct empirical formula.
Step-by-step explanation:
The question asks for the empirical formula of ninhydrin based on its composition by percent of carbon, hydrogen, and oxygen. To find this, we first convert the percentage composition to moles using the atomic masses of the elements (C: 12.01 g/mol, H: 1.008 g/mol, O: 16.00 g/mol). Then, we divide by the smallest number of moles to find the simplest whole-number ratio.
- Carbon: 65.88% → (65.88 g/12.01 g/mol)
- Hydrogen: 3.40% → (3.40 g/1.008 g/mol)
- Oxygen: 3.56% → (28.09 g/16.00 g/mol)
However, the percentages given for carbon, hydrogen, and oxygen only add up to 72.84%, which implies the presence of other elements, likely nitrogen, in ninhydrin. Without the exact percentage of nitrogen, we cannot accurately determine the empirical formula. The student needs to provide composition data for all the elements in ninhydrin to find the correct empirical formula.
Based on the given options and without complete information, none can be confirmed as the correct empirical formula for ninhydrin. If the remaining composition were indeed nitrogen, we would need the percentage of nitrogen to resolve this.