question_answer

When vapours of X were gradually heated from \[25{}^\circ C\]at atmospheric pressure, the colour was found to deepen at first and then fades as the temperature was raised above \[{{160}^{o}}C\]. At \[{{600}^{o}}C\],the vapours were almost colourless, but the colour deepened When the pressure was raised at this temperature. Identify X.

A)  Bromine.

B)  A mixture of nitrogen dioxide and dinitrogen tetroxide.

C)  Pure nitrogen dioxide.

D)  Pure dinitrogen tetroxide.