Answer:
0.972
Step-by-step explanation:
The balanced chemical equation for the reaction is:
3 NaOH + H3PO4 → Na3PO4 + 3 H2O
From the equation, we can see that for every 1 mole of H3PO4 reacted, 3 moles of water are produced. Therefore, we need to first calculate how many moles of H3PO4 are present in 4.30 g of NaOH:
molar mass of NaOH = 23.0 g/mol + 16.0 g/mol + 1.0 g/mol = 40.0 g/mol
moles of NaOH = 4.30 g / 40.0 g/mol = 0.108 mol
According to the balanced equation, 3 moles of water are produced for every 1 mole of H3PO4. Therefore, we can calculate how many moles of water are formed as follows:
moles of H3PO4 = 3/1 * 0.108 mol = 0.324 mol
moles of water = 3/1 * 0.324 mol = 0.972 mol
Therefore, 0.972 moles of water are formed when reacting 4.30 g of sodium hydroxide with phosphoric acid.