Answer:
We need 36.45 grams of Mg
Step-by-step explanation:
Step 1: Data given
Moles of Mg3N2 produced = 0.500 moles
Molar mass of Mg = 24.3 g/mol
Molar mass of Mg3N2 = 256.41 g/mol
Step 2: The balanced equation
3Mg + N2 → Mg3N2
Step 3: Calculate moles of Mg
For 3 moles of Mg we need 1 mol of N2 to produce 1 mol of Mg3N2
For 0.500 moles Mg3N2 we need 3*0.500 moles = 1.500 moles of Mg
Step 4: Calculate mass of Mg
Mass Mg = moles Mg * molar mass Mg
Mass Mg = 1.500 moles * 24.3 g/mol
Mass Mg = 36.45 grams