Determine the empirical formula for a compound with 15.8% carbon and 84.2% sulfur? square

To determine the empirical formula for a compound with 15.8% carbon and 84.2% sulfur, we need to follow these steps:

1. Convert the percentages to grams.
2. Convert the grams to moles.
3. Determine the simplest whole number ratio of moles.

Step 1: Convert the percentages to grams.
Assume we have 100 grams of the compound.
- Carbon: 15.8 grams
- Sulfur: 84.2 grams

Step 2: Convert the grams to moles.
- Moles of Carbon (C): $\frac{15.8 \text{ g}}{12.01 \text{ g/mol}} = 1.316 \text{ moles}$
- Moles of Sulfur (S): $\frac{84.2 \text{ g}}{32.06 \text{ g/mol}} = 2.625 \text{ moles}$

Step 3: Determine the simplest whole number ratio of moles.
Divide each mole value by the smaller of the two values to find the simplest ratio:
- Ratio for Carbon: $\frac{1.316}{1.316} = 1$
- Ratio for Sulfur: $\frac{2.625}{1.316} \approx 2$

Therefore, the empirical formula for the compound is $\text{CS}_2$.