Determine the number of grams of NH3 produced by the reaction of 3.5g of hydrogen gas with sufficient nitrogen gas

1. Write the balanced equation.
2. Convert what you have (3.5 g) into mols. Mols = grams/molar mass.
3. Use the coefficients in the balanced equation to convert mols of what you have (hydrogen gas) to mol of what you want (NH3).
4. Convert mols NH3 to grams NH3.
g NH3 = mols NH3 x molar mass NH3.

Post your work if you get stuck.