To calculate the mass of 2.50 mol of sulfur, we need to know the molar mass of sulfur. The molar mass of sulfur (S) is 32.06 g/mol.

The mass (m) of a substance is calculated by multiplying the number of moles (n) by the molar mass (M).

$$m = n \times M$$

Substituting the given values, we get:

$$m = 2.50 \text{ mol }S \times 32.06 \text{ g/mol }$$

$$m = 80.15 \text{ g}$$

Therefore, the mass of 2.50 mol of sulfur is 80.15 grams.