The equations given in the problem introduction can be added together to give the following reaction: overall: n2o4→2no2 however, one of them must be reversed. which one?

Reverse the  reaction

Explanation:

Reactions:

Overall:

As can be seen, in the overall reaction we have in the reactants like in the second reaction and in the products. The is in the first reaction but as a reactant so we need to reverse that reaction:

Combining:

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explanation: