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Question
A compound contains 87.5% by mass of nitrogen and 12.5% by mass of hydrogen. Determine the empirical formula of this compound.
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Solution
Empirical formula of the compound is as :
| Element | Atomic mass | Percentage | Relative number of moles | Simplest mole ratio | Whole number ratio |
| N | 14 | 87.5 | 87.5/14 = 6.25 | 6.25/6.25 = 1 | 1 |
| H | 1 | 12.5 |
12.5/1 |
12.5/6.25 = 2 | 2 |
So, the empirical formula of the compound is NH2.
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