Final answer:
The empirical formula of the compound with the given composition of 29.4% calcium, 23.5% sulphur, and 47.1% oxygen is CaSO4.
Step-by-step explanation:
The empirical formula of a compound can be determined by analyzing the composition of the compound. In the given question, the compound has the following composition: 29.4% calcium, 23.5% sulphur, and 47.1% oxygen by mass. To find the empirical formula, we need to convert the mass percentages into moles. Assuming a 100 gram sample, we have 29.4 grams of calcium, 23.5 grams of sulphur, and 47.1 grams of oxygen. The calculated moles are as follows:
Calcium: 29.4g / 40.08 g/mol = 0.732 mol
Sulphur: 23.5g / 32.06 g/mol = 0.734 mol
Oxygen: 47.1g / 16.00 g/mol = 2.944 mol
Now, we divide each of the moles by the smallest number of moles, which is 0.732:
Calcium: 0.732 mol / 0.732 mol = 1.00
Sulphur: 0.734 mol / 0.732 mol = 1.00
Oxygen: 2.944 mol / 0.732 mol = 4.02
Rounding these numbers to the nearest whole number, we get the empirical formula: CaSO4