`NO_(2)` turns acidic `KI`-starch paper blue, why?

SO_(3) does not turn starch iodate paper blue.

SO_(3) does not turn starch iodate paper blue.

A substance X when heated with sulphuric acid liberates a gas which turns starch paper blue. The substance is

Name the gas that turns moist starch iodide paper blue black.

Name the gas that turns moist starch iodide paper blue black.

A substance X when heated with conc. H_2SO_4 , liberates a gas which turns starch paper blue. The substance X is

A salt when heated with H_(2)SO_(4) librates violet gas which turns starch paper blue, salt may be

A substance X when heated with conc.\(H_{2}SO_{4}\) liberates a gas which turns starch paper blue. The substance "X" is?

A solution of a sodium salt gives yellow precipitate with both Pb^(2+) and Ag^(+) ions. Moreover, the acidified solution of sodium salt with KNO_(2) liberates a coloured gas which turns starch paper blue. The anion is :