In Dumas method for the estimation of $\mathrm{N}_{2}$, the sample is heated with copper oxide and the gas evolved is passed over :

JEE Main · 2023 · 31 Jan 2023 · Shift 2 · Practical and Analytical Chemistry

In Dumas method for the estimation of

N_{2}

, the sample is heated with copper oxide and the gas evolved is passed over :

(A)Ni
(B)Copper gauze✓ Correct
(C)Pd
(D)Copper oxide

Answer: (B)

Solution

In the Dumas method the nitrogenous compound is heated with copper oxide in a stream of carbon dioxide, liberating nitrogen together with carbon dioxide and water vapour. Small amounts of oxides of nitrogen that form alongside must be reduced back to free nitrogen before the gas is collected, and this is achieved by passing the mixture over heated copper gauze.

JEE Main · 2023 · 31 Jan 2023 · Shift 2 · Single correct option

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