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For the estimation of nitrogen, 1.4 g of an organic compound was digested by Kjeldahl method and the evolved ammonia was absorbed in 60 mL of M/10 sulphuric acid. The unreacted acid required 20 mL of M/10 sodium hydroxide for complete neutralization. The percentage of nitrogen in the compound is -

1. 10%
2. 3%
3. 5%
4. 6%

Correct answer: 10%

Solution

The correct option is 10% because the amount of ammonia produced from the digestion of the organic compound can be calculated based on the neutralization of the unreacted sulfuric acid with sodium hydroxide. This calculation reveals that the nitrogen content in the original sample corresponds to 10% of its weight.

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