MHT CET Chemistry Question (2026) — Solution

Step-by-step solution

Potassium nitrite (KNO_2) is an ionic compound and provides nitrite ions (NO_2^-) in the solution. The nitrite ion is an ambidentate nucleophile with two donor sites: oxygen and nitrogen. Since the K-O bond is ionic, the negative charge on the oxygen atom is available for nucleophilic attack on the alkyl halide. This results in the formation of an alkyl nitrite (R-O-N=O) as the major product. In contrast, silver nitrite (AgNO_2) has a covalent Ag-O bond, making the lone pair on the nitrogen atom act as the nucleophile, which leads to the formation of a nitroalkane (R-NO_2). Therefore, potassium nitrite is used to convert an alkyl halide into an alkyl nitrite. Answer: Potassium nitrite