Calculate the mass of water that is formed by the interaction of 20 g of sodium hydroxide with phosphoric acid.

1. The equation of interaction of sodium hydroxide with phosphoric acid has the form:

3NaOH + H3PO4 = Na3PO4 + 3H2O;

2.Calculate the chemical amount of sodium hydroxide:

n (NaOH) = m (NaOH): M (NaOH);

M (NaOH) = 23 + 16 + 1 = 40 g / mol;

n (NaOH) = 20: 40 = 0.5 mol;

3. Determine the amount of water formed:

n (H2O) = n (NaOH) = 0.5 mol;

4.calculate the mass of water:

m (H2O) = n (H2O) * M (H2O);

M (H2O) = 2 + 16 = 18 g / mol;

m (H2O) = 0.5 * 18 = 9 g;

Answer: 9 g.