Which blue liquid is obtained on reacting equimolar amounts of two gases at – ${30}^{\circ }C$

Q. Which blue-liquid is obtained on reacting equimolar amounts of two gases at $-{30}^{o}C$?

Q. A pale blue liquid which is obtained by reacting equimolar mixture of two gases at -${30}^{o}C$ is :

Q. The nitrogen oxide(s) that contain(s) $N-N$ bond(s) is/are

Q. The nitrogen oxides that contain N – N bond(s) is: