When 56 of calcium is reacted with nitrogen gas 32 of calcium nitride is produced What is the percent yield of calcium nitride for this reaction?

The equation for this reaction is 3 Ca + N2 -> Ca3N2. The gram molecular mass of Ca3N2 is 148.25, and the gram Atomic Mass of Ca is 40.08. Therefore, the amount of Ca3N2 that could theoretically be formed from 56 grams of calcium is 56(148.25)/(3 X 40.08) or 69.10 grams. The percentage yield is therefore 100(32)/(69.10) or 46 %, to the justified number of significant digits.