Question

What is the theoretical yield of li3n in grams when 12.5 g of li is heated with 34.1 g of N₂?

Answer 1

The theoretical yield of Li3N when 12.5 g of Li reacts with 34.1 g of N2 is determined using stoichiometry with a balanced chemical equation, molar masses of reactants, limiting reactant concept, and subsequent calculation.

Step-by-step explanation:

The theoretical yield of lithium nitride (Li3N) can be calculated using the stoichiometry of the balanced chemical equation when lithium (Li) is heated with nitrogen (N2). First, the balanced chemical equation for the reaction is:

6 Li + N2 → 2 Li3N

The molar masses of the reactants are:

• Lithium (Li) = 6.94 g/mol
• Nitrogen (N2) = 28.02 g/mol

The molar mass of lithium nitride (Li3N) is:

• Li3N = 34.83 g/mol

To find the theoretical yield:

1. Convert the mass of Li and N2 to moles.
2. Determine the limiting reactant.
3. Use the stoichiometry of the reaction to calculate the moles of Li3N produced by the limiting reactant.
4. Convert the moles of Li3N to grams to find the theoretical yield.

Since the molar ratio of Li to Li3N is 6:2 (or 3:1), you'd calculate the moles of Li and N2 using their respective molar masses, then apply the ratio to find which reactant is the limiting one. Calculation of the theoretical yield of Li3N follows from the moles of the limiting reactant.