Question

In Kjeldahl method, sample containing nitrogen is digested with:

• A. \( \text{Conc. NaOH} \)
• B. \( \text{Fuming HNO}_3 \)
• C. \( \text{Conc. H}_2\text{SO}_4 \)
• D. \( \text{Strong NH}_3 \text{ solution} \)

Hint:

The Kjeldahl method is fundamental in food, agriculture, and environmental analysis for nitrogen quantification.

Answer 1

The Correct Option is C

The Kjeldahl method is a widely used technique for nitrogen determination in organic samples. Concentrated \( \text{H}_2\text{SO}_4 \) is used to digest the sample, converting organic nitrogen into ammonium sulfate. A catalyst such as selenium or copper is often added to enhance digestion efficiency.