Pure nitric acid on longstanding turns to yellow due to the formation of

Options

A. `O_(2)NO` and `H_(2)O`
B. `O_(2),NO_(2)` and `H_(2)O`
C. `NO,NO_(2) and H_(2)O`
D. `N_(2)O,O_(2) and H_(2)O`

Answer

B

Explanation

Pure nitric acid is highly unstable, and hence, undergoes decomposition forming `NO_(2)`, `H_(2)O` and `O_(2)`. `NO_(2)` is a reddish brown gas. Dilute solution of `NO_(2)` appears as yellow colour.
`4HNO_(3) to 4ON_(2) + 2H_(2)O + O_(2)`