Question

Which of the following has arranged in increasing oxidation numbers of nitrogen ?

1. NH₃ < N₂O₅ < NO < N₂
2. NO₂⁺ < NO₃^- < NO₂^- < N₃^-
3. NH₄^{+ <} N₂H₄ < NH₂OH < N₂O
4. NO₂ < NaN₃ < NH₄⁺ < N₂O

Answer 1

$$\begin{gathered} N{H_4}^{+} \\ x+4\hspace{0.17em}\left(1\right)=1 \\ x=-3 \\ {N}_2{H}_4 \\ 2x=4\left(1\right)=0 \\ 2x=-4 \\ x=-2 \\ N{H}_{2}OH \\ x+2\left(1\right)+1(-2)+1\left(1\right)=0 \\ x=-1 \\ {N}_{2}O \\ 2x+1(-2)=0 \\ x=1 \end{gathered}$$
Option 3 is the right answer.
Oxidation state are
-3 < - 2 < -1 < 1