Question

A Colourless crystalline compound $(A)$ , is warmed with $Al$ and $NaOH$ , solution gives a gas which produces fumes with $HCl$ , brown ppt. When passed through Nessler's reagent and is oxidised to a colourless gas when passed over heated $CuO$ . The latter does not support to combustion, however, $.$ , continues burning in it producing white solid. The compound $(A)$ , when heated along gives a brown coloured gas and another gas $(B)$ , which is essential for living beings, leaving behind a yellow solid $(C)$ . The solid $(C)$ , gives the following reactions.

(i) It dissolves in dil. ${HNO}_{3}$ , giving a colourless solution which gives white ppt.On addition of dilute $HCl$ , which is soluble in hot and reappears on cooling.

(ii) When heated in presence of air, the yellow solid $(C)$ , changes to red powder, Identify $(A), (B)$ and $(C)$ , And the equations involved.

(i) It dissolves in dil. ${HNO}_{3}$ , giving a colourless solution which gives white ppt.On addition of dilute $HCl$ , which is soluble in hot and reappears on cooling.

(ii) When heated in presence of air, the yellow solid $(C)$ , changes to red powder, Identify $(A), (B)$ and $(C)$ , And the equations involved.

Accepted Answer

The nitrate ion present in the salt, liberates amminia gas with aluminium in the presence of sodium hydroxide,

$8 Al + 3 {NO}_{3}^{-} + 18 H_{2} O + 5 {OH}^{-} ⇌ 8 Al (OH)_{4}^{-} + 3 {NH}_{3} $

${NH}_{3} + HCl \to {NH}_{4} Cl$ (White fumes)

${NH}_{3} + K_{2} {HgI}_{4} \to [{NH}_{2} HgO . HgI]$ (Brown $p p t$ , of Iodide of $M i l l o n' s$ , base $.$ )

${NH}_{3} + CuO \to N_{2} + H_{2} O + Cu$ ( $N_{2}$ , is a colourless gas $.$ )

$Mg + N_{2} \to {Mg}_{3} N_{2}$ (White Solid)

$Pb {({NO}_{3})}_{2} (A) \overset{∆}{\to} PbO + {NO}_{2} + O_{2}$

$PbO$ = Yellow solid, ${NO}_{2}$ = Brown gas, $O_{2}$ = gas essential for life

$B = O_{2}$

$C = P b O$

(i) $PbO + {HNO}_{3} \to Pb {({NO}_{3})}_{2} + H_{2} O Pb {({NO}_{3})}_{2} + 2 HCl \to {PbCl}_{2} + 2 {HNO}_{3}$ ( ${PbCl}_{2}$ , is a white $p p t$ $.$ )

(ii) $PbO + O_{2} \to {Pb}_{3} O_{4}$ (Red powder)

Column I	Column II
(A) Its partial hydrolysis does not change oxidation state of central atom	(1) $He$
(B) It is used in modern diving apparatus	(2) ${XeF}_{6}$
(C) It is used to provide inert atmosphere for filling electrical bulbs	(3) ${XeF}_{4}$
(D) Its central atom is in ${sp}^{3} d^{2}$ hybridisation	(4) $Ar$

Embibe Experts Solutions for Chapter: The p-Block Elements, Exercise 4: EXERCISE-4

Embibe Experts Chemistry Solutions for Exercise - Embibe Experts Solutions for Chapter: The p-Block Elements, Exercise 4: EXERCISE-4

Questions from Embibe Experts Solutions for Chapter: The p-Block Elements, Exercise 4: EXERCISE-4 with Hints & Solutions

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