Nitric Acid: Preparation, Structure, Properties and Uses

All of the given statements are true for nitric acid except

In brown ring test for nitrate ions, brown ring is formed having composition

Metal which become passive with conc. ${\mathrm{HNO}}_3$ is

${\mathrm{HNO}}_2$ on disproportionation gives ${\mathrm{HNO}}_3$ and

The product $\text{'}\mathrm{P}\text{'}$ will be

${\mathrm{NH}}_3+{\mathrm{O}}_2\underset{\mathrm{\Delta }}{\overset{\mathrm{Pt}}{\to }}\mathrm{A}+{\mathrm{H}}_2\mathrm{O}$
$\mathrm{A}+{\mathrm{O}}_2⟶\mathrm{B}$
$\mathrm{B}+{\mathrm{H}}_2\mathrm{O}⟶\mathrm{C}+\mathrm{D}$
$\mathrm{A}, \mathrm{B}, \mathrm{C}$ and $\mathrm{D}$ respectively are

In brown ring test for nitrate ions, brown ring is formed having composition 

Concentrated nitric acid turns the colour of the skin into-

The brown ring test for nitrates depends upon

When ${\mathrm{PbO}}_2$ reacts with concentrated ${\mathrm{HNO}}_3$, the gas evolved is

The oxidation state of nitrogen in ${\mathrm{HNO}}_3$ is:

When the copper metal is treated with a cold and dilute nitric acid, it forms

Which of the following does not produce ${\mathrm{NO}}_2$ gas with conc. ${\mathrm{HNO}}_3$ ?

Select the correct statement from the following:

When copper is heated with conc. ${\mathrm{HNO}}_3$ it produces
 

In the brown ring test, brown colour of the ring is due to

A brown ring is formed in the ring test for ${\mathrm{NO}}_3^{-}$ ion. It is due to the formation of

Select the correct statement.

${\mathrm{FeSO}}_4$ forms brown ring with
 

In which of the following reactions, reaction of silver with the given acids lead to the formation of compound & silver, along with liberation of gas ?