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Question
Calculate the percentage of sodium in sodium aluminium fluoride (Na3AIF6).
[F = 19, Na = 23, Al = 27]
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Solution
Molecular weight of sodium aluminium fluoride (Na3AIF6 ) = 210
Now, 210 parts by weight of Na3AIF6 contains = 69 parts by weight of sodium
So, 100 parts will contain = 69 x 100 / 210 = 32.8 or 33‰
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