Final answer:
Approximately 0.0870 moles of H2 are needed to react with 2 grams of Na, assuming a 1:1 molar ratio for the reaction of sodium with hydrogen gas.
Step-by-step explanation:
To determine how many moles of H2 are needed to react with 2 grams of Na, we first need to convert the mass of sodium to moles. The atomic mass of sodium (Na) is approximately 22.99 g/mol. So, we use the formula:
moles Na = mass (g) / molar mass (g/mol).
Rewriting it with our values, we have:
moles Na = 2 g / 22.99 g/mol = 0.0870 moles Na (approximately).
Now, analyzing the reaction between sodium (Na) and hydrogen gas (H2), there is generally a 1:1 molar ratio for reactions involving alkali metals and hydrogen gas, unless stated otherwise in a balanced chemical equation. Since we have approximately 0.0870 moles of Na and the ratio is 1:1, we will need the same number of moles of H2, which is approximately 0.0870 moles as well.
However, the problem detail mentions a reaction with an incorrect product (NaCl), so I'll disregard that and remain focused on the direct query about the reaction of Na with H2