Question

The redox reaction among the following is:

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Answer 1

Combination of dinitrogen with dioxygen at $2000K$

$N_{2\left(g\right)}+O_{2\left(g\right)}\to 2N{O}_{\left(g\right)}$

Oxidation state of $N$ in $N_2=0$
Oxidation state of $N$ in $NO=+2$

Oxidation state of $O$ in $O_2=0$
Oxidation state of $O$ in $NO=-2$

Here, the oxidation state of $N$ is changing from zero or native state to $+2$ state and for oxygen it is changing from $0$ to $-2$ state. Therefore $N$ is getting oxidised and $O$ is getting reduced. Hence, combination of dinitrogen with dioxygen is a redox reaction.