Question

$0.243$ g of a organic compound containing nitrogen was Kjeldahlized and ammonia gas evolved was absorbed in $90.3$ ml of $\frac{1}{10}NHCI$. unused acid required $20$ ml of $0.2NNaOH$ for complete neutralization . percentage of nitrogen in the sample is?

• A. $30.12\%$
• B. $3.012\%$
• C. $60.245\%$
• D. $60.24\%$

Answer 1

The correct option is A $30.12\%$

For Kjeldahl method,

$\%$ $Nitrogen=\frac{1.4\times (N_{acid}{V}_{acid}-N_{base}{V}_{base})}{\text{weight of organic compound}}$

$=\frac{1.4\times (\frac{1}{10}\times 90.3-0.2\times 20)}{0.243}$

$\approx 30.12\%$

Hence, this is the answer.