ACIDIC RADICALS ( CONC. SULPHURIC ACID GROUP)

   DATE

                                                 EXPERIMENT NO._________

Aim :  To test the presence of  Chloride ( Cl- ) in the given salt .

S.No.	EXPERIMENT	OBSERVATION	INFERENCE
1.	Physical tests: (i) Colour  (ii) Odour (iii) Solubility
2.	Take 1g of salt in a dry test tube and 4-5 ml of conc.H2SO4 .	Colourless gas ( HCl ) is evolved.	May be  Cl - .
3.	Bring a glass rod dipped in NH4OH near the mouth of the test tube when gas is being evolved in the above test.	Dense white fumes are evolved.	May be Cl -.
4.	SILVER NITRATE TEST :--- To the aqueous solution of the salt, add Silver nitrate solution.	White precipitate is obtained which is soluble in excess of Ammonium hydroxide.	Cl – confirmed.
5.	CHROMYL CHLORIDE TEST :------ Take a pinch of the solid salt with an equal amount of solid potassium Dichromate. Heat the mixture with conc. H2SO4. Pass the gas evolved through NaOH solution. Acidify the yellow solution with Acetic acid & then add Lead Acetate solution.	Red vapours of Chromyl Chloride ( CrO2Cl2) are evolved. Solution turns yellow. Yellow precipitate is obtained.	Cl – confirmed.

RESULT  : The given salt contains Chloride (Cl - ) in it .

REACTIONS INVOLVED  :---------

(i)  6 Cl – (s)  + 3H2SO4  (conc.)    ----------------> 6 HCl (g) + 3 SO42- (aq)

(ii)   HCl (g ) + NH4OH  (aq)        ----------------->  NH4Cl  (g) +  H2O (l)

      

(iii)  Cl – (aq) + AgNO3(aq)         ----------------->  AgCl (s) + NO3- (aq)

       AgCl (s) +  NH4OH  (aq)      ----------------->   [Ag(NH3)2]Cl  (s)   + H2O (l)

                                                                                    Diammine silver (I)

                                                                                   Chloride ( Soluble ).

(iv)  4 Cl - (S) + K2Cr2O7 (S) + 3H2SO4  (conc.)   ------------> 2 CrO2Cl2 (g) + K2SO4 (aq)  

                                                                                                     +  3H2O(l)  + 2 SO42-  (aq)

     CrO2Cl2 (g) + 4 NaOH(aq)----------------->   Na2CrO4 (aq) + 2 NaCl (aq) + 2 H2O(l)

     Na2CrO4 (aq) + (CH3COO)2Pb (aq) ------------>      PbCrO4(s)    + 2 CH3COONa (aq)

                                                                                           Lead Chromate 

                                                                                          ( Yellow ppt.)

          

        

         DATE

                                                 EXPERIMENT NO._________

Aim :  To test the presence of  Bromide ( Br - ) in the given salt .

S.No.	EXPERIMENT	OBSERVATION	INFERENCE
1.	Physical tests: (i) Colour  (ii) Odour (iii) Solubility
2.	Take 1g of salt in a dry test tube and 4-5 ml of conc.H2SO4 .	Reddish brown gas ( Br2) is evolved.	May be Br - .
3.	SILVER NITRATE TEST :- To the aqueous solution of the salt, add Silver nitrate solution.	Pale yellow precipitate is obtained which is partially  soluble in excess of Ammonium hydroxide solution.	Br – confirmed.
4.	LAYER TEST   ( CHLORINE WATER AND CS2 or CCl4 TEST )   :----------- Acidify a portion of the aqueous solution of the salt with dil.HCl and then add 1-2 ml of Cs2 or CCl4 and excess of Chlorine water , shake  vigorously and allow to stand.	Yellow or orange colour in Cs2 or CCl4 layer.	Br – confirmed.

RESULT  : The given salt contains Bromide (Br- ) in it .

REACTIONS INVOLVED  :---------

(i)  Br - (s)  + H2SO4  (conc.)    ---------------->   HBr(g) + HSO42- (aq)

      2HBr(g) + H2SO4 (conc.)      ---------------->    Br2 (g)  + SO2(g)  + 2H2O (l)

      

(ii)  Br – (aq) + AgNO3(aq)         ----------------->  AgBr (s) + NO3- (aq)

                                                                                  Pale yellow ppt.

       AgBr (s) +  2NH4OH  (aq)    ----------------->   [Ag(NH3)2]Br  (aq)     + H2O (l)

                                                                                    Diammine silver (I)

                                                                                   Bromide 

(iii)  2Br – (aq) +   Cl2 (aq)         ---------------->  2 NaCl (aq) + Br2 (l)

                          Chlorine water

                                                                                                                                                                              

DATE

                                                 EXPERIMENT NO._________

Aim :  To test the presence of  Iodide ( I - ) in the given salt .

S.No.	EXPERIMENT	OBSERVATION	INFERENCE
1.	Physical tests: (i) Colour  (ii) Odour (iii) Solubility
2.	Take 1g of salt in a dry test tube and 4-5 ml of conc.H2SO4 .	Violet vapours are ( I2)  evolved.	May be I - .
3.	SILVER NITRATE TEST :--------- To the aqueous solution of the salt, add Silver nitrate solution.	Yellow precipitate is obtained which is insoluble in excess of Ammonium hydroxide solution.	I– confirmed.
4.	LAYER TEST   ( CHLORINE WATER AND CS2 or CCl4 TEST )   :------ Acidify a portion of the aqueous solution of the salt with dil.HCl and then add 1-2 ml of Cs2 or CCl4 and excess of Chlorine water , shake  vigorously and allow to stand.	Violet colour in Cs2 or CCl4 layer.	I – confirmed.

RESULT  : The given salt contains Iodide (I - ) in it .

REACTIONS INVOLVED  :---------

(i)  I - (s)  + H2SO4  (conc.)    ---------------->   HI (g) + HSO42- (aq)

      2HI (g) + H2SO4 (conc.)      ---------------->    I2 (g)  + SO2(g)  + 2H2O (l)

      

(ii)  I – (aq) + AgNO3(aq)         ----------------->    AgI (s) + NO3- (aq)

                                                                               yellow ppt.

       AgI (s) +  2NH4OH  (aq)    ----------------->   [Ag(NH3)2]I  (s)     + H2O (l)

                                                                                    Diammine silver (I)

                                                                                   Bromide (insoluble)

(iii)  2I – (aq) +   Cl2 (aq)      ---------------->  2 NaCl (aq) + I2 (l)

                            Chlorine water

                                                                                                                                                                              

DATE

                                                 EXPERIMENT NO._________

Aim :  To test the presence of  Nitrate ( NO3- )  in the given salt .

S.No.	EXPERIMENT	OBSERVATION	INFERENCE
1.	Physical tests: (i) Colour  (ii) Odour (iii) Solubility
2.	Take  salt in a dry test tube and 4-5 ml of conc.H2SO4 .	Light brown coloured fumes of NO2 gas are evolved.	May be  NO3 -.
3.	Add copper turnings to the contents of the test tube in previous step & heat the test tube.	Dark brown fumes are intensified.	NO 3- is confirmed.
4.	RING TEST :------------- Take salt solution in a test tube ,add freshly prepared FeSO4 solution and incline the test tube at 450 ,then add conc. H2SO4 along the side of the inclined test tube.	A dark blackish-brown ring of  [ Fe(NO)SO4] is formed at the junction of two liquids.	NO 3- is confirmed.

RESULT  : The given salt contains Nitrate ( NO3- )   in it .

REACTIONS INVOLVED  :---------

(i)   NO3- (s)   + dil.H2SO4  (aq)         ---------------->    HSO4- (aq)  + HNO3 (aq)

                                4 HNO3 (aq)          ------------------>   4NO2 (g) + O2 (g) + 2H2O (l)

     2NO3- (aq)  + 4H2SO4  (aq)   + 3Cu ---------------->  3 CuSO4(aq) + SO42- (aq) + 

                                                                                               2 NO(g)    + 4 H2O (l)

                                     2NO(g) + O2 (g) ----------------->    2NO2 (g)

                                                                                              BROWN FUMES

(ii)  NO3- (aq)   + dil.H2SO4  (aq)          ---------------->   HSO4- (aq)  + HNO3 (aq)

   6 FeSO4 + 3 H2SO4 (aq) + 2 HNO3 (aq) ------------->  3 Fe2(SO4)3 + 4 H2O(l) + 2 NO(g)

                                  FeSO4(aq) + NO(g) ----------------> [ Fe(NO)SO4]

                                                                                              BROWN RING

                                                                                     ( NITROSO FERROUS SULPHATE)

                                                                               

DATE

                                                 EXPERIMENT NO._________

Aim :  To test the presence of  Acetate ( CH3COO- )  in the given salt .

S.No.	EXPERIMENT	OBSERVATION	INFERENCE
1.	Physical tests: (i) Colour  (ii) Odour (iii) Solubility
2.	Take 1g of salt in a dry test tube and 4-5 ml of conc.H2SO4 .	Vinegar like odour.	May be  CH3COO- .
3.	OXALIC ACID TEST :----- Mix a little of the salt with solid Oxalic acid on a watch glass. Prepare a paste of it with a few drops of water. Rub the mixture between fingers and smell.	Vinegar smell is observed.	CH3COO- is confirmed.
4.	Ester Test : Take a pinch of the salt & add 2-3 drops of conc. H2SO4  & 4-5 drops of Ethyl Alcohol. Warm the mixture in a water bath for 10 min. Cool & pour the contents into 10 ml of aqueous  Na 2CO3 solution in a beaker.	A fruity smell appears due to the formation of Ester.	CH3COO- is confirmed.
5.	FERRIC CHLORIDE TEST :------ To  aqueous solution of the given salt ,add a few drops of neutral Fecl3 solution to it.	Deep red colouration is produced.	CH3COO- is confirmed.

RESULT  : The given salt contains  Acetate ( CH3COO- )   in it .

REACTIONS INVOLVED  :---------

(i)   CH3COO- (s)   +  H2SO4  (conc.)   ---------------->   CH3COOH (g) + HSO42- (aq)

(ii)   C2H2O4 (l) + CH3COO- (aq)           ---------------->   CH3COOH (g)  + C2O42- (aq)

      

(iii)  3 CH3COO- (aq)  +  FeCl3 (aq)    ---------------->   Fe(CH3COO)3(aq)  + 3Cl- (aq)

                                                                                             Ferric chloride  ( red colour )