Question

Match the column I with column II and mark the appropriate choice.

	Column I		Column II
(A)	Laughing gas	(i)	Hydrazoic acid
(B)	Anhydride of $HNO_3$	(ii)	Nitrous oxide
(C)	Anhydride of $HPO_3$	(iii)	Nitrogen pentoxide
(D)	Acid hydride of nitrogen	(iv)	Phosphorus pentoxide

• A. $(A) \to (i)$, $(B) \to (ii)$, $(C) \to (iii)$, $(D) \to (iv)$
• B. $(A) \to (iv)$, $(B) \to (i)$, $(C) \to (ii)$, $(D) \to (iii)$
• C. $(A) \to (ii)$, $(B) \to (iii)$, $(C) \to (iv)$, $(D) \to (i)$
• D. $(A) \to (iii)$, $(B) \to (iv)$, $(C) \to (i)$, $(D) \to (ii)$

Answer 1

Answer: (C)

(A) Laughing Gas $\longrightarrow $ Nitrous oxide.
As this gas sometimes generates a feeling of euphoria due to which a person wants to laugh after smelling it.
(B) Anhydride of $HNO _{3} \longrightarrow $ anhydride means a compound obtained after water has been removed from other compounds.
From $HNO _{3}, H _{2} O$ can't be removed so, if we take $2\left( HNO _{3}\right)$
$\longrightarrow H _{2} N _{2} O _{6} \,\, \xrightarrow[H_2O]{} N _{2} O _{5}$ (nitrogen penta-oxide)
(C) Anhydride of $HP O _{3}$
Similarly as above if we take
$2\left[ HPO _{3}\right]= H _{2} P _{2} O _{6} \xrightarrow{- H _{2} O } P _{2} O _{5}$ (Phosphorus Pentaoxide)
(D) Acid Anhydride of nitrogen.
Acid Anhydride is formed by the combination of two acid structures with an ion of a water molecule.
Hydrazine reacts with nitrous acid giving acid anhydride of nitrogen, i.e, hydrazoic acid with loss of 2 molecules of water.
$N _{2} H _{4}+ HNO _{2} \longrightarrow HN _{3}+2 H _{2} O$