Question

Given below are two statements, one is labelled as Assertion (A) and other one labelled as Reason (R).
Assertion (A): For determination of total nitrogen in soil, the sample is usually digested with concentrated \(\text{H}_2\text{SO}_4\) in the presence of catalyst mixture consisting of \(\text{K}_2\text{SO}_4\) and \(\text{CuSO}_4\) in the ratio of 10:1.
Reason (R): The \(\text{K}_2\text{SO}_4\) is used to raise the boiling point of \(\text{H}_2\text{SO}_4\) that promote the oxidation of organic matter and conversion of organic N to \(\text{NH}_4^+\)-N, while the \(\text{CuSO}_4\) acts as a catalyst and hastens the breaking down of organic matter and conversion of N to \((\text{NH}_4)_2\text{SO_4\).
Choose the correct answer from the options given below:

• A. Both (A) and (R) are true and (R) is the correct explanation of (A).
• B. Both (A) and (R) are true but (R) is NOT the correct explanation of (A).
• C. (A) is true but (R) is false.
• D. (A) is false but (R) is true.

Hint:

In Kjeldahl digestion:
- \(\text{K}_2\text{SO}_4\) acts as a boiling point elevator.
- \(\text{CuSO}_4\) (or Selenium powder) acts as a catalyst to accelerate the digestion process.

Answer 1

The Correct Option is A