chemistry help please!

Question

Consider the following reaction:

SO₂ + 2 H₂S → 3 S + 2 H₂O

If 4.95 g of SO₂ reacts via this reaction in excess H₂S, what mass (in g) of H₂O will be produced?

Answer 1

molar mass SO₂ = 64.1 g / mol

molar mass H₂O = 18 g / mol

4.95 g SO₂ x 1 mol SO₂ / 64.1 g = 0.0772 mols SO₂

SO₂ + 2H₂S ==> 3S + 2H₂O .. balanced equation

0.0772.....xs............0...........0..........Initial

-0.0772.......................+2x0.0772....Change

0..................................0.154..........Equilibrium

So, when reaction is over, there will be 0.154 mols H₂O formed

To convert this to mass (grams), we use the molar mass of H₂O:

0.154 mols H₂O x 18 g / mol = 2.78 g H₂O (3 sig. figs.)