Question

A colourless, neutral, paramagnetic oxide of Nitrogen $'P'$ on oxidation gives reddish brown gas $Q$. $Q$ on cooling gives colourless gas $R$. $R$ on reaction with P gives blue solid $S$. Identify $P , Q , R , S$, respectively

• A. $N _{2} O\, NO\, NO _{2} \,N _{2} O _{5}$
• B. $N _{2} O\, NO _{2}\, N _{2} O _{4} \,N _{2} O _{3}$
• C. $NO \,NO _{2} \,N _{2} O _{4}\, N _{2} O _{3}$
• D. $NO \,NO\, N _{2} O _{4} \,N _{2} O _{5}$

Answer 1

The Correct Option is C

Let's solve the question by assessing the given options and considering the chemical properties of nitrogen oxides:

The question asks for a colorless, neutral, and paramagnetic oxide of nitrogen. Let’s analyze the properties of each option:

1. N_2O (Nitrous oxide):
   • Colorless: Yes
   • Neutral: Yes
   • Paramagnetic: No, it is diamagnetic.
2. NO (Nitric oxide):
   • Colorless: Yes
   • Neutral: Yes
   • Paramagnetic: Yes, due to the unpaired electron.
3. NO_2 (Nitrogen dioxide):
   • Colorless: No, it is reddish-brown.
   • Neutral: It is acidic.
   • Paramagnetic: Yes, due to the unpaired electron.
4. N_2O_4 (Dinitrogen tetroxide):
   • Colorless: Yes, in liquid form at low temperatures.
   • Neutral: It is acidic.
   • Paramagnetic: No, it is diamagnetic as it dimerizes from NO₂ in low temperatures.
5. N_2O_5 (Dinitrogen pentoxide):
   • Colorless: Yes
   • Neutral: No, it is acidic.
   • Paramagnetic: No, it is diamagnetic.
6. N_2O_3 (Dinitrogen trioxide):
   • Colorless: No, it is blue.
   • Neutral: No, it is acidic.
   • Paramagnetic: No, it is diamagnetic.

Based on this analysis, NO matches the properties of being colorless, neutral, and paramagnetic due to the presence of an unpaired electron.

Therefore, the correct answer is NO, making the correct choice: NO \,NO _{2} \,N _{2} O _{4}\, N _{2} O _{3}.