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Question
Find the total percentage of oxygen in magnesium nitrate crystal Mg(NO3)2.6H2O.
[H = 1, N = 14, O = 16, Mg = 24]
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Solution
Molecular mass of Mg (NO3)2.6H2O is = 256
Now, 256 parts by weight of crystal contains 192 parts by weight of oxygen.
So 100 parts by weight will contain = 192 x 100/256 = 75‰
Hence, total percentage of oxygen in magnesium nitrate crystal Mg(NO3)2.6H2O is 75‰
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