Gases emitted during volcanic activity often contain high concentrations of hydrogen sulfide and sulfur dioxide. These gases may react to produce deposits of sulfur according to the equation: 2 H₂S(g) + SO₂(g) → 3 S(s) + 2 H₂O(g)
For the complete reaction of 6.41 mol of hydrogen sulfide:

Question

Quizplus · Accepted Answer

According to the balanced chemical equation, 2 moles of hydrogen sulfide react with 1 mole of sulfur dioxide to produce 3 moles of sulfur and 2 moles of water vapor. Therefore, for the complete reaction of 6.41 mol of hydrogen sulfide, we need half as many moles of sulfur dioxide, i.e., 3.205 mol, to produce 4.815 mol of sulfur and 3.205 mol of water vapor. The molar mass of sulfur is 32.06 g/mol, so 4.815 mol of sulfur has a mass of 154.15 g or 308 g (rounded to two significant figures).

Gases Emitted During Volcanic Activity Often Contain High Concentrations of Hydrogen