How many molecules of water are produced if 2.0 grams of sodium sulfate are produced in the reaction of sulfuric acid and sodium hydroxide (water is also a product).

Answer 1

First, always start with a correctly balanced equation for the reaction taking place:

H₂SO₄(aq) + 2NaOH(aq) ==> Na₂SO₄(aq) + 2H₂O(l) ... balanced equation

sulfuric acid....sod.hydrox.......sod.sulfate........water

Next, use the stoichiometry of the balanced equation and the molar mass of Na₂SO₄ (142 g / mol), to find the moles of H₂O produced:

2.0 g Na₂SO₄ x 1 mol Na₂SO₄ / 142 g x 2 mol H₂O / 1 mol Na₂SO₄ = 0.0282 mols H₂O produced

Finally, using Avogadro's number, convert moles H2O to molecules of H2O:

0.0282 mols H₂O x 6.022x10²³ molecules / mole = 1.70x10²² molecules H₂O