Question

Match the items of Column I with Column II and choose the correct option from the codes given below.

Column I(Test for element)		Column II(Products involved in the chemical reaction)
A	Test for nitrogen	1	${\left(N{H}_4\right)}_{3}P{O}_4\cdot 12Mo{O}_3$ Ammonium phosphomolybdate
B	Test for sulphur	2	$F{e}_4{\left[Fe(CN{)}_6\right]}_3\cdot x{H}_{2}O$ Prussian blue
C	Test for both nitrogen and sulphur	3	$AgX$
D	Test for halogens	4	$[Fe(SCN){]}^{2+}$ Blood red
E	Test for phosphorus	5	$PbS$ Black

• A. $A-(1),B-(2),C-(3),D-(4),E-(5)$
• B. $A-(2),B-(5),C-(4),D-(3),E-(1)$
• C. $A-(5),B-(3),C-(4),D-(2),E-(1)$
• D. $A-(4),B-(2),C-(3),D-(1),E-(5)$

Answer 1

Answer: (B)

The correct match is
$A\to 2,B\to 5,C\to 4,D\to 3,E\to 1$
A. Test for nitrogen $:6C{N}^{-}+F{e}^{2+}⟶{\left[Fe(CN{)}_6\right]}^{4-}$
$3{\left[Fe(CN{)}_6\right]}^{4-}+4F{e}^{3+}\stackrel{x{H}_{2}O}{\to }\underset{\text{Prussian blue}}{F{e}_4{\left[Fe(CN{)}_6\right]}_3\cdot x{H}_{2}O}$
B. Test for sulphur : $S^{2-}+P{b}^{2+}⟶\underset{\text{Black}}{\mathrm{PbS}}$
$S^{2-}+{\left[Fe(CN{)}_{5}NO\right]}^{2-}⟶\underset{\text{Violet}}{\left[Fe(CN{)}_{5}NO{S}^{4-}\right]}$
C. Test for both nitrogen and sulphur :
$Na+C+N+S⟶NaSCN$
$F{e}^{3+}+SC{N}^{-}⟶\underset{\text{Blood red}}{[Fe(SCN){]}^{2+}}$
$NaSCN+2Na⟶NaCN+N{a}_{2}S$
D. Test for halogen $:X^{-}+A{g}^{+}⟶AgX$
E. Test for phosphorus :
$N{a}_{3}P{O}_4+3HN{O}_3\to H_{3}P{O}_4+3NaN{O}_3$
$H_{3}P{O}_4+\underset{\text{Ammonium molybdate}}{12(N{H}_4{)}_{2}Mo{O}_4}+21HN{O}_3\to$
$\underset{\text{Ammonium phosphomolybdate}}{(N{H}_4{)}_{3}P{O}_4\cdot 12Mo{O}_3}+21N{H}_{4}N{O}_3+12H_{2}O$