According to the formula it should be +5 but according to its structure shouldn't it be +4? How is it +5 then?
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2$\begingroup$ $5\cdot(-2) + 2\cdot(+5) = 0$ $\endgroup$– Klaus-Dieter WarzechaFeb 18, 2016 at 7:44
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$\begingroup$ But according to the structure it should be + 4 $\endgroup$– rishabh guptaFeb 18, 2016 at 8:32
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1$\begingroup$ No. Why do you think so? $\endgroup$– aventurinJul 2, 2016 at 17:46
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1$\begingroup$ A coordinate bond gives a formal charge of +1 to N, implying that it effectively gets a raise in oxidation state by +2 $\endgroup$– SubZeroMar 25, 2017 at 17:59
1 Answer
It is +5 .Even by the structure.
Notice that it is a resonance structure of:
Now one of the bonds are coordinate bonds where nitrogen donates BOTH its electrons to oxygen (otherwise, oxygen cannot have a single bond without a negative charge and no peroxy type linkage).
So, while determining oxidation state from the structure :
O.N=+2+2+1=+5
References: https://en.wikipedia.org/wiki/Dinitrogen_pentoxide
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1$\begingroup$ Your second image is better since it shows formal charges. $\endgroup$– JanJul 2, 2016 at 18:10
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$\begingroup$ True, but that's not much of an improvement. Evidently, I picked it up for representation purpose. $\endgroup$– VarunJul 4, 2016 at 2:37
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4$\begingroup$ Oh, I always advocate properly assigning formal charges to all atoms that need them, which is why I wouldn’t have upvoted your answer if only the first structure were shown ;) $\endgroup$– JanJul 5, 2016 at 0:11