Question

A solution of colourless salt on boiling with excess `NaOH` produces a non-flammable gas. The gas evolution ceases after sometime upon addition of `Zn` dust to the same solution, the gas evolution restarts. The colourless salt (s) is (are).
A. `NH_(4)NO_(3)`
B. `NH_(4)NO_(2)`
C. `NH_(4)Cl`
D. `(NH_(4))_(2)SO_(4)`

Answer 1

Correct Answer - A::B
`NH_(4)NO_(3)` or `NH_(4)NO_(2)+NaOH rarr NH_(3) ("non flammable gas")+H_(2)O+NaNO_(3)`
`Zn` react with this solution & produce nacent hydrogen which can reduce `NO_(3)^(-)//NO_(2)^(-)` in ammonia.