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(II) mmonia! N*! (colourless! pungent odour) evolved #hich indicates that a N*3 compound #as

heated. +mmonia turns red litmus paper blue and forms #hite fumes #ith *'l (g),

(III) 4ulphur dioxide! 42! (colourless! choking odour) evolved! indicates that a sulphide! 42-! sulphite!

42-! or sulphate! 42-

! #as burnt. +42 turns orange 5 2'r267*3 green and purple 5/n7*

3 

colourless,

(I8) Nitrogen dioxide! N2! (reddish bro#n! pungent odour) evolved indicates that a nitrate! N-! #as

burnt. +N2 turns blue litmus paper red,

(8) Iodine! I2! (purple vapour) evolved indicates iodide ions! I -.

(8I) No reaction indicates that an ionic compound #ith high lattice energ" #as heated.

   4.  Action of dilute HCl 

  (I) '2- or *'-: production of e9ervescence! gas turns lime #ater cloud"

  (II) 42-: production of 42

  (III) Nitrite! N-2! production of N2.

SEE CATIONS ON OTHER DOCUMENT

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ANIONS

Carbonates 

- ddition of dilute *'l +see above, '2-

(s)  3 2*3

(a;)  < *2 (l)  3 '2 (g).

- ddition of a;ueous =arium salt – #hite precipitate (ppt) of barium carbonate =a' is formed. %he

ppt is soluble in dilute acids #ith the evolution of '2.

Nitrates

- 'oncentrated sulphuric acid in the presence of copper turnings - N2 is evolved> the *N(a;) acid

formed reacts #ith the copper to produce N2 and the resulting solution is greenish blue due to the

presence of copper (II) ions! 'u23(a;). *N (a;)  3 'u(s)  < 'u (N)2(a;)  3 2N2 (g)  3 2*2 (l).

- ?sing luminium or $inc po#der in sodium h"droxide solution - N* (g) is evolved on heating a nitrate#ith this mixture.

Sulphate ions

- ?sing =arium chloride! =a'l2 (a;)! or =arium nitrate! =a(N)2(a;)! solution. In the presence of dilute *'l or

*N! a #hite ppt of =a4 is formed #hich is soluble in #arm concentrated *'l. =a23 (a;)  3 42-

(a;)  < =a4 (s).  %his test is carried out in the presence of dilute *'l or dilute *N to prevent

the carbonates and sulphites from precipitating out.

- ?sing lead (II) ions! 1b23 - #hite ppt of lead (II) sulphate is formed #hich is soluble in #arm7hot

concentrated *24. 1b23(a;)  3 42-(a;)  < 1b4(s).

Sulphite ions

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- ?sing dilute *'l7*24  - 4ulphur dioxide! 42(g)! is evolved on #arming. 423

(a;)  3 2*3

(a;)  < 42(g) 

3 *2(l).

- ?sing =arium solutions - #hite ppt of =a4 is formed #hich is readil" soluble in dilute *'l #ith the

evolution of 42. =a23

(a;)  3 42-

(a;)  < =a4 (s).

- ?sing silver nitrate solution – #hite ppt of silver sulphate! g24 is formed. It turns from gre" to

black on #arming due to the decomposition to silver. 2g3(a;)  3 42-(a;)  < g24(s).

- ?sing lead (II) ions! 1b23 - #hite ppt of lead (II) sulphite is formed #hich is soluble in dilute *N.

1b23 (a;)  3 42- (a;)  < 1b4 (s).

Chromate ions -- Cr!- 4

- ?sing silver nitrate solution – red bro#n ppt of g2'r is formed. %he ppt is soluble in ammonia N*

(a;) and in dilute nitric acid! *N. 2g3

(a;)  3 'r2-

(a;)  < g2'r(s).

- ?sing =arium solution - pale "ello# ppt of =a'r is formed. %he ppt is insoluble in ethanoic acid!

'*'* but soluble in strong acids. =a23(a;)  3 'r2-(a;)  < =a'r(s).

- ?sing lead (II) ions! 1b23 - "ello# ppt of lead (II) chromate is formed #hich is insoluble in ethanoic

acid! '*'* but soluble in nitric acid! *N. 1b23 (a;)  3 'r2- (a;)  < 1b'r (s).

Chloride ion

- ?sing silver nitrate solution gN(a;). - #hite ppt of g'l is formed #hich is soluble in N*(a;)! to form

the complex ion g(N*)32. g3(a;)  3 'l-(a;)  < g'l(s).

- ?sing conc. *24. – *"drogen chloride is evolved as a colourless pungent vapour. It turns blue litmus

paper red and forms #hite fumes #ith N*(g). *24(l)  3 'l-(a;)  < *'l(g)  3 *4-(a;).

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- ?sing lead (II) ions – #hite ppt of 1b'l2 is formed. %he ppt dissolves on heating and reprecipitates on

cooling. 1b23 (a;)  3 2'l- (a;)  < 1b'l2 (s).

Bromide ion 

- ?sing silver nitrate solution gN(a;). - n o9 #hite ppt of g=r is formed #hich is sparingl" soluble inN*(a;) and insoluble in dilute nitric acid! *N. g3(a;)  3 =r-(a;)  < g=r(s).

- ?sing conc. *24. – @eddish bro#n vapours of bromine and h"drogen bromide are evolved. *"drogen

bromide is initiall" formed but oxidised to bromine *24(l)  3 =r-(a;)  < *=r(g)  3 *4

-(a;).

- ?sing lead (II) ions – #hite ppt of 1b=r2 is formed. %he ppt dissolves on heating and reprecipitates on

cooling. 1b23 (a;)  3 2=r- (a;)  < 1b=r2 (s).

"odide ion

- ?sing silver nitrate solution gN(a;). - "ello# or cream ppt of gI is formed #hich is insoluble in

N*(a;) and insoluble in dilute *N. g3(a;)  3 I-(a;)  < gI(s).

- ?sing conc. *24. – Iodine is liberated ass a black or violet ppt. n #arming violet vapours of iodine

are evolved. *"drogen iodide is initiall" formed but is then oxidi$ed to iodine. *24(l)  3 I-(a;)  < *I(g) 

3 *4-(a;). 2*I(g)  3 () < I2(s)  3 *2(l).

- ?sing lead (II) ions – "ello# ppt of 1bI2 is formed. It is soluble in excess of the iodide solution.

1b23 (a;)  3 2I- (a;)  < 1bI2 (s)! 1bI2(s)  3 2I-(a;)  < +1bI,23(a;).

 

ualitative nal"sis /'astle 20&0+%"pe text, 1age A