Concept:Ammonium nitrate is an ionic compound composed of two distinct polyatomic ions: the ammonium cation (\( NH_4^+ \)) and the nitrate anion (\( NO_3^- \)). The nitrogen atoms in these two ions exist in completely different oxidation states.
Solution:- For the Ammonium ion (\( NH_4^+ \)): Let \( x \) be the oxidation state of N.
\( x + 4(+1) = +1 \implies x = -3 \).
- For the Nitrate ion (\( NO_3^- \)): Let \( y \) be the oxidation state of N.
\( y + 3(-2) = -1 \implies y - 6 = -1 \implies y = +5 \).
- Therefore, the oxidation states of the two nitrogen atoms are \( -3 \) and \( +5 \), respectively.
Why other options are incorrect:If one erroneously tried to average the nitrogens as \( N_2H_4O_3 \), they might guess something else, but chemically, the ions are distinct and must be calculated separately.
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