Chemistry question help

Question

For the following reaction, 5.72 grams of magnesium nitride are mixed with excess water. The reaction yields 8.69 grams of magnesium hydroxide.

Mg₃N₂ (s) + 6H₂O (l)  3Mg(OH)₂ (aq) + 2NH₃ (aq)

(1) What is the theoretical yield of magnesium hydroxide?	grams
(2) What is the percent yield for this reaction?	%

Answer 1

100.929 g Mg3N2 = 1 mol Mg3N2

1 mol Mg3N2 = 3 mol Mg(OH)2

1 mol Mg(OH)2 = 58.319 g Mg(OH)2

Convert g Mg3N2 to mol Mg3N2, then mol Mg(OH)2, then grams Mg(OH)2

5.72 g Mg3N2 ( ^{1 mol Mg3N2} / _{100.929 g Mg3N2}) (^{3 mol Mg(OH)2} / _{1 mol Mg3N2}) (^{58.319 g Mg(OH)2} / _{1 mol Mg(OH)2})

=9.915 g Mg(OH)2

This is the theoretical yield.

The experimental yield is given as 8.69 g Mg(OH)2

Percent yield formula:

%yield=(^{experimental yield} / _{theoretical yield})100

%yield=(^8.69/_9.915)100

%yield=87.6% yield Mg(OH)2