In: Chemistry
In a combination reaction, if 1.34794 moles of magnesium is heated with 0.2638 moles of nitrogen, to form magnesium nitride, how many grams of magnesium nitride will be produced?
The balanced equation of combustion of magnesium in nitrogen is
3 Mg + N2 Mg3N2
From the above equation it is clear that 1 mole nitrogen will react completely with 3 moles of magnesium.
We have here 0.2638 moles of nitrogen.
If 1 mole nitrogen will react completely with 3 moles of magnesium, then 0.2638 moles of nitrogen will completely react with (3 x 0.2638) = 0.7914 moles magnesium.
We have therefore in excess of (1.34794 - 0.7914) = 0.55654 moles magnesium
Therefore the limiting reagent here is N2
Now, 1 mole of N2 will produce 1 mole of Mg3N2
Therefore, 0.2638 moles of N2 will produce = 0.2638 moles of Mg3N2
Molar mass of Mg3N2 = 3 x 24.3 + 2 x 14 = 100.9 g/mol
Therefore the amount of Mg3N2 will be produced = 0.2638 x 100.9 = 26.62 g