Question

Out of the following redox reactions
I. $NH _{4} NO _{3} \xrightarrow{\Delta}N _{2} O +2 H _{2} O$
II. $NH _{4} NO _{2} \xrightarrow{\Delta} N _{2}+2 H _{2} O$
III. $PCl _{5} \xrightarrow{\Delta} PCl _{3}+ Cl _{2}$
disproportionation is not shown in

• A. I and II
• B. II and III
• C. I and III
• D. I, II and III

Answer 1

Answer: (D)

I. $\underset{-3}{ NH _{4}^{+}} \underset{+5}{ NO _{3}^{-}} \longrightarrow \underset{+1}{ N _{2} O }+2 H _{2} O$
It is $a$ redox reaction but not $a$ disproportionation reaction. Since, different N-species are involved.
II. $\underset{-3}{ NH _{4}}^{+} \underset{+3}{ NO _{2}}^{-} \longrightarrow \underset{0}{ N _{2}}$
same as (I)
III.$\underset{+5-1}{PCl _{5}} \longrightarrow \underset{+3-1}{ PCl _{3}}+\underset{0}{ Cl _{2}}$
Thus, it is also not a disproportionation reaction.