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Question
Calculate the percentage of nitrogen in aluminium nitride. [Al = 27, N = 14]
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Solution
Molecular mass of aluminium nitride (AIN3) = 27 + 14 x 3 = 69
Now, 69 parts by weight of aluminium nitride contains = 42 parts by weight of nitrogen
So, 100 parts will contain = 42 x 100 / 69 = 60.86‰
Hence, the percentage of nitrogen in aluminium nitride is 60.86‰
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