Arrange the given compounds in order of decreasing oxidation state of nitrogen
(A) \(N_2\)
(B) \(NO\)
(C) \(HNO_3\)
(D) \(NH_4Cl\)
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → \(HNO_3 > NO > N_2 > NH_4Cl\)
The oxidation state of an atom in a compound is found by taking H as +1 and O as −2 (in these compounds) and making the sum equal to the charge on the species. Nitrogen shows oxidation states from −3 to +5.
(A) N2: an element, so the oxidation state is 0.
(B) NO: x + (−2) = 0, so x = +2.
(C) HNO3: (+1) + x + 3(−2) = 0, so x = +5.
(D) NH4Cl: in the \( \ce{NH4^{+}} \) ion, x + 4(+1) = +1, so x = −3.
Shortcut: \( \ce{NH4Cl} \) (−3) must come last; only Option (2) ends with it.