There can be three possible answers to this question: the amount of moles of SO₂ gas needed to react with 6.41 mol H₂S, and the amount of S and H₂O gas produced.
Amount of SO₂:
6.41 mol H₂S (1 mol SO₂/2 mol 2 mol H₂S) = 3.205 moles SO₂ gas
Amount of S:
6.41 mol H₂S (3 mol S/2 mol 2 mol H₂S) = 9.615 moles S solid
Amount of H₂O:
6.41 mol H₂S (2 mol H₂O/2 mol 2 mol H₂S) = 6.41 moles H₂O gas