A solution of colourless salt H on boiling with axcess `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) H is (are)

Options

A. `NH_(4)NO_(3)`
B. `NH_(4)NO_(2)`
C. `NH_(4)Cl`
D. `(NH_(4))_(2)SO_(4)`

Answer

A, B

Explanation

The colourless salt H may be either `NH_(4)NO_(3) or NH_(4)NO_(2)` and the non-inflammable gas is `NH_(3)`
(a) `{:(NH_(4)NO_(3) + NaOH overset(Delta)rarr underset("Non-inflammable gas")(NH_(3)) + NaNO_(3) + H_(2)O),(4 Zn + 7 NaOH + NaNO_(3) overset(Delta)rarr underset("Sod. zincate")(4Na_(2)ZnO_(2)) + underset("Gas evolution restarts")(NH_(3)) + 2H_(2)O):}`
(b) `{:(NH_(4)NO_(2) + NaOH overset(Delta)rarr NH_(3) + NaNO_(2) + H_(2)O),(3 Zn + 5 NaOH + NaNO_(2) overset(Delta)rarr 3Na_(2)ZnO_(2) + NH_(3) + H_(2)O):}`