A pollutant in smog is nitrogen dioxide, NO 2 . The gas has a reddish brown colo
ID: 815552 • Letter: A
Question
A pollutant in smog is nitrogen dioxide, NO2. The gas has a reddish brown color and is responsible for the red-brown color associated with this type of air pollution. Nitrogen dioxide is also a contributor to acid rain because when rain passes through air contaminated with NO2, it dissolves and undergoes the following reaction:
3NO2(g) + H2O ? NO(g) + 2H+(aq) + 2NO3-(aq).
In this reaction, which element is reduced and which is oxidized?
Which element is the oxidizing agent and which is the reducing agent?
Explanation / Answer
oxidation state of N in NO2 is +4; in NO is +2 and in NO3- is +5
Therefore, in the above reaction,
element oxidised is N and reduced is N
Both oxidizing and reducing agent is N.