In Kjeldahl's method for estimation of nitrogen, CuSO4 acts as :
- catalytic agent
- hydrolysis agent
- reducing agent
- oxidising agent
Answer
(1) catalytic agent
Solution
Kjeldahl digestion: organic compound + conc. H2SO4 (+ K2SO4 + CuSO4) (NH4)2SO4
∵ CuSO4 only speeds up the digestion and is not used up (K2SO4 raises the boiling point of the acid)
⇒ CuSO4 is a catalyst
Answer: (1)