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Question
- The percentage composition of a gas is:
Nitrogen 82.35%, Hydrogen 17.64%. - Find the empirical formula of the gas. [N = 14, H = 1]
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Solution
a.
| Element | % composition | At. Wt. | Relative no. of atoms | Simplest ratio |
| Nitrogen | 82.35 | 14 | `82.35/14` = 5.88 | `5.88/5.88` = 1 |
| Hydrogen | 17.64 | 1 | `17.64/1` = 17.64 | `17.64/5.88` = 3 |
b. Simplest ratio of whole numbers = N : H = 1 : 3
Hence, the empirical formula is NH3.
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