All nitrates on heating with conc. `H_(2)SO_(4)` in presence of paper pellet evolve `NO_(2)` gas. The function of the paper pellet is `:`

Options

A. reduce `HNO_(3)` to `N_(2)`
B. to reduce `HNO_(3)` to `NO`
C. to reduce `HNO_(3)` to `NO_(2)`
D. to reduce `HNO_(3)` to `NH_(3)`

Answer

3

Explanation

`2NO_(3)^(-)+H_(2)SO_(4)+CrarrrH_(2)CO_(3)+2NO_(2)+SO_(4)^(2-)`