Final answer:
To determine the number of grams of H2 formed when 4.52 moles of Na reacts with an excess of water, use the balanced chemical equation and the molar mass of H2.
Step-by-step explanation:
To determine the number of grams of H2 formed when 4.52 moles of Na reacts with an excess of water, we first need to balance the chemical equation. The balanced equation for the reaction between Na and water is:
2Na + 2H2O → 2NaOH + H2
From the balanced equation, we can see that for every 2 moles of Na that react, 1 mole of H2 is formed. Therefore, if 4.52 moles of Na react, we expect to produce half that amount of moles of H2.
Number of moles of H2 = (4.52 moles of Na) / 2 = 2.26 moles of H2
To convert the moles of H2 to grams, we need to use the molar mass of H2, which is 2 g/mol.
Mass of H2 = (2.26 moles of H2) * (2 g/mol) = 4.52 grams of H2