We have been teached how to balance chemical reactions with oxidation numbers in school, but somehow I can't understand it.
This is the equation to balance $$\ce{Cu(s) + NO3−(aq) + H+(aq) -> Cu^2+(aq) + NO2(g) + H2O(l)}$$
At first I looked at the oxidation numbers. The only oxidation numbers that change are $\ce{Cu}:\ 0\ \rightarrow \ 2+$ and $\ce{N}:\ 1-\rightarrow \ 4+$, both are oxidized.
Then I'm a bit lost. In a typical redox reaction I would create partial reactions for both oxidation and reduction, but nothing is reduced in this reaction. I made two partial reactions with $\ce{Cu}$ and $\ce{N}$ being oxidized, but I think that it's not how it should be done. I came to a very different result than my book.
Is there anyone who knows how I should balance this reaction? I'm a bit lost.