Zn gives `H_(2)` gas with `H_(2)SO_(4)` and HCl but not with `HNO_(3)` because-

Options

A. Zn acts as an oxidising agent when it reacts with `HNO_(3)`
B. `HNO_(3)` is weaker acid than `H_(2)SO_(4)` and HCl
C. In electrochemical series. Zn is above hydrogen
D. `NO_(3)^(-)` is reduced in preference to hydronium ion

Answer

D

Explanation

Zinc gives `H_(2)` gas with dil `H_(2)SO_(4)//HCl` but not with `HNO_(3)` because in `HNO_(3),NO_(3)^-` ion is reduced and give `NH_(4)NO_(3),N_(2)O,NO and NO_(2)` (based upon the concentration of `HNO_(3)`)
`[Zn+underset(("nearly 6%"))(2HNO_(3)) to Zn(NO_(3))_(2)+2H]xx4`
`HNO_(3)+8H to NH_(3)+3H_(2)O`
`NH_(3)+HNO_(3) to NH_(4)NO_(3)`
`4Zn+10HNO_(3) to 4Zn(NO_(3))_(2)+NH_(4)NO_(3)+3H_(2)O`
Zn is on the top position of hydrogen in electrochemical series. so Zn displaces `H_(2)` from dilute `H_(2)SO_(4)` and HCl with liberation of `H_(2)`.
`Zn+H_(2)SO_(4) to ZnSO_(4)+H_(2)`