Question

Fill in the blanks.
The reaction of nitrogen with oxygen, to form nitric oxide is an _________ reaction.

Answer 1

At much higher temperatures, nitrogen reacts with oxygen to form nitric oxide, but this takes a considerable spark of energy. In the upper atmosphere during a lightning storm, nitrogen and oxygen react and the resulting nitric oxide further reacts with water to form nitric acid.

Hence, it is an endothermic reactions.