June 21, 2012

GENERAL PROCEDURE for THE SYSTEMATIC ANALYSIS OF A SIMPLE SALT

I. PRELIMINARY TESTS
S. No.
EXPERIMENT
OBSERVATION
INFERENCE
1
SOLUBILITY
A little of the salt is shaken with water.
1) Soluble
1) May be Sulphate, Nitrate, Chloride or Ammonium Carbonate.
2) Insoluble
2) May be Carbonate or Sulphide.
2
ACTION OF HEAT:
A small amount of the salt is heated gently in a dry test tube.
1) Colourless, odourless gas turning Lime water milky.
1) May be Carbonate.
2) Decripitation occurs with evolution of reddish brown gas.
2) May be Nitrate.                          
3) Salt sublimes with evolution of pungent smelling gas giving dense white fumes with a glass rod dipped in conc HCl.
3) May be Ammonium.
4) The white salt turns yellow on heating.
4) May be Zinc.


5) No characteristic change.
5) Absence of Carbonate, Nitrate,    Ammonium and Zinc.
3
FLAME TEST:
A small amount of the salt is made into a paste with conc. HCl in a watch glass and introduced into the non-luminous part of the Bunsen flame.
1) Bluish colour flame.
1)  Presence of Copper.

2) Brick red flame.
2) Presence of Calcium.
          
3) Grassy green flame.
3) Presence of Barium.

4)  No characteristic coloured flame.
4) Absence of Copper, Calcium and Barium.
4
ASH TEST:
A filter paper is soaked into a paste of the salt with conc. HCl / HNO3 and Cobalt Nitrate solution in a watch glass and burnt.
1) Green ash.
1) Presence of Zinc.
2) Blue ash.
2) Presence of Aluminium.
3) Pink ash.                 
3) Presence of Magnesium.
4) No characteristic coloured ash.
4) Absence of Zinc, Aluminium and Magnesium.

II. TESTS FOR ACID RADICALS
5
ACTION OF DIL HCl
To a small amount of dilute HCl the salt is added.
1) Brisk effervescence of colourless, odourless gas turning Lime water milky.
1) Carbonate is confirmed.
2) Rotten egg smelling gas turning Lead acetate paper black.
2) Sulphide is confirmed.
3) No characteristic change.
3) Absence of Sulphide and Carbonate.
6
COPPER TURNINGS TEST:
A small amount of the salt is heated with Copper Turnings / Filter paper ball and a few drops of conc. Sulphuric acid.
1) Reddish brown gas is evolved.
1) Presence of Nitrate.

2) No reddish brown gas is evolved.
2) Absence of Nitrate.
7
CHROMYL CHLORIDE TEST:
To a small amount of the salt a pinch of Potassium Dichromate is added and heated with few drops of conc. Sulphuric acid.
1) Red orange vapours evolved are passed through water to get a yellow solution, which on adding Lead acetate forms a yellow precipitate.
1) Chloride is confirmed.







2) No Red orange vapours.
2) Absence of chloride.






8
ACTION OF NaOH:
A small amount of the salt is heated with Sodium Hydroxide.
1) Pungent smelling gas forming dense white fumes with a glass rod dipped in conc. HCl and also turns red Litmus paper blue.
1) Presence of Ammonium.
2) No pungent smelling gas.
2) Absence of Ammonium.

III. TESTS WITH SODIUM CARBONATE EXTRACT
9. PREPARATION OF SODIUM CARBONATE EXTRACT:
A small amount of salt is mixed with twice the amount of sodium carbonate and 20ml of distilled water is added, boiled for 10 minutes, cooled and filtered. The filtrate is called “SODIUM CARBONATE EXTRACT”.
S. No
EXPERIMENT
OBSERVATION
INFERENCE
10
BARIUM CHLORIDE TEST:
To a few drops of the extract, dilute Hydrochloric Acid is added until the effervescence ceases and 2 ml of Barium chloride solution is added.
1) A white precipitate, insoluble in conc. HCl.
1) Sulphate is confirmed. 
2) No white precipitate.
2) Absence of Sulphate
11
SILVER NITRATE TEST:
To a few drops of the extract dilute Nitric Acid is added until the effervescence ceases and 2 ml of Silver Nitrate solution is added.
1) A curdy white precipitate, soluble in excess of Ammonium hydroxide.
1) Presence of Chloride.
2) A black precipitate.
2) Presence of Sulphide.
3) No precipitate.
3) Absence of chloride/ sulphide.
12
BROWN RING TEST:
To a few drops of extract dilute Sulphuric acid is added until the effervescence ceases, then freshly prepared FeSO4 is added and then conctrated Sulphuric acid is added drop by drop along the sides of the test tube.
1) Brown ring is formed at the junction of the two layers.
1) Nitrate is confirmed.

2) No brown ring.
2) Absence of Nitrate.

IV. IDENTIFICATION OF THE BASIC RADICALS
13. PREPARATION OF ORIGINAL SOLUTION:
The original solution is prepared by dissolving the salt in_______________#
Water  (When the salt is water soluble)
#  Dil. HCl  or Dil. HNO3 (When the salt is water insoluble)
14. GROUP IDENTIFICATION
S. No
EXPERIMENT
OBSERVATION
INFERENCE
1
To a few drops of the original solution 2 ml of dilute HCl is added.
1) White precipitate.
1)  Presence of First Group. (Lead).
2) No characteristic precipitate.
2) Absence of First Group (Lead).
2
To a few drops of the original solution 2 ml of dilute HCl is added and H2S gas is passed.
1) Black precipitate.
1)  Presence of Second   Group (Copper).
2) No characteristic precipitate.
2) Absence of Second Group (Copper).
3
To a few drops of the original solution 1 ml NH4Cl and 2 ml NH4OH solutions are added.
1) Gelatinous white precipitate.
1)  Presence of Third Group (Aluminium).
2) No characteristic precipitate.
2) Absence of Third Group (Aluminium).
4
To a few drops of the original solution 1 ml NH4Cl and 2 ml NH4OH solutions are added and H2S gas is passed.
1) Dirty white precipitate.
1)  Presence of Fourth Group (Zinc).
2) No characteristic precipitate.
2) Absence of Fourth Group (Zinc).
5
To a few drops of the original solution 1 ml NH4Cl, 2 ml NH4OH and 2 ml (NH4)2CO3  solutions are added.
1) White precipitate.
1) Presence of Fifth Group (Calcium or Barium).
2) No characteristic precipitate.
2) Absence of Fifth Group (Calcium and Barium).
6
To a few drops of the original solution 1 ml NH4Cl, 2 ml NH4OH and 2 ml Di Sodium Hydrogen Phosphate are added.
1) White precipitate.
1) Presence of Sixth Group (Magnesium).

2) No characteristic precipitate.
2) Absence of Sixth Group (Magnesium).

V. CONFIRMATORY TESTS FOR BASIC RADICALS
S. No
EXPERIMENT
OBSERVATION
INFERENCE
TEST FOR AMMONIUM
1
To a few drops of the original solution Sodium Hydroxide and Nessler’s reagent are added.
Reddish brown precipitate.
Ammonium is confirmed.

First group  -  LEAD
1
To a few drops of the original solution Potassium Chromate is added.
Yellow precipitate.
Lead is confirmed.
2
To a few drops of the original solution Potassium Iodide is added.
Yellow precipitate soluble in hot water which reappears as golden yellow spangles on cooling.
Lead is confirmed.

Third group - ALUMINIUM
1
To a few drops of the original solution Sodium Hydroxide is added in drops to excess.
White precipitate soluble in excess of Sodium hydroxide.
Aluminium is confirmed.
2
To a few drops of the original solution Ammonium Hydroxide and Aluminon reagent are added.
A bright red lake.
Aluminium is confirmed.
Fourth group - ZINC
1
To a few drops of the original solution Sodium Hydroxide is added in drops to excess.
White precipitate soluble in excess of Sodium hydroxide.
Zinc is confirmed.
2
To a few drops of the original solution Potassium Ferro cyanide is added.
White precipitate soluble in excess of Sodium hydroxide & insoluble in dilute acid.
Zinc is 
confirmed.
Fifth group - CALCIUM
1
To a few drops of the original solution Potassium Chromate is added.
No precipitate.
Calcium is confirmed.
2
To a few drops of the original solution Ammonium Hydroxide and Ammonium Oxalate are added.
White precipitate insoluble in Acetic acid.
Calcium is confirmed.
Fifth group - BARIUM
1
To a few drops of the original solution Potassium Chromate is added.
Yellow precipitate, soluble in acid.
Barium is confirmed.
2
To a few drops of the original solution Dilute Sulphuric Acid is added.
White precipitate insoluble in Acetic acid.
Barium is confirmed.
Sixth group - MAGNESIUM
1
To a few drops of the original solution Sodium Hydroxide is added in drops to excess.
White precipitate, insoluble in excess of Sodium hydroxide.
Magnesium is confirmed.
2
To a few drops of the original solution Magneson reagent is added.
Blue precipitate.
Magnesium is confirmed.
** Colourless salts only be given for practicals. Points expected in the practical exam. alone posted here.
RESULT
                The given simple salt contains
1. Basic Radical            : __________________
2. Acid Radical             : __________________

 The given simple salt is : ____________________________________

55 comments:

  1. u could have added some more.....

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  2. crimson red flame--strontium

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    Replies
    1. Thank you Nandhu. It's for State board student. Strontium is not in this practical syllabus.

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    2. Hello I'm gokul I have one question . it's that is there a group separation and confirmatory test for ammonium chloride ,ammonium sulphate,ammonium carbonate.

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    3. Yes. But procedure differ for TN Board, CBSE, KV, College, etc.,
      http://cbseportal.com/Chemistry/Salt-Analysis-of-Cations-and-Anions-Chemistry

      https://sites.google.com/site/cbsehomework/practical/chemprac/salt-analysis/inorganic

      http://amrita.olabs.edu.in/?sub=73&brch=7&sim=180&cnt=2

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    4. Add colour and appearance of the given salt as experiment 1

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  3. can put some specific salt procedure

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  4. lead acetate test missing

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    Replies
    1. On what basis, basic radicals are classified in to groups

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    2. On what basis, basic radicals are classified in to groups

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    3. Classification is based on whether a cation reacts with the group reagents - hydrochloric acid, hydrogen sulphide, ammonium hydroxide and ammonium carbonate - by the formation of precipitates or not. It can therefore be said that classification of the most common cations is based on the differences of solubilities of their chlorides, sulphides, hydroxides and carbonates.

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  5. Ash test is done with concentrated nitric acid not hydrochloric acid

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  6. +2 chemstryla intha test padichu enappaaaaaaaaaaaaa puniyaaaaaammmmmmmm...

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    Replies
    1. 1. The illiterate of the future will not be the person who cannot read. It will be the person who does not know how to learn. - Alvin Toffler

      2. Either write something worth reading or do something worth writing. - Benjamin Franklin

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  7. why there is no confirmative test for group2 copper

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    Replies
    1. Experiment

      To a few drops of original solution as potassium ferrocyanide.

      Observation:
      Chocolate brown precipitate

      Experiment 2:
      To a few drops of original solution add Sodium Sulphide solution
      Observation
      Black precipitate is formed

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  8. YOURS MATERIAL IS VERY USEFUL

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  9. Copper turning + conc H2SO4 test , it is better to mention the test for the reddish brown gas evolved from the reaction with freshly prepared FeSO4 solution.

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  10. thank you so much !
    it really helps for TN - H.S.L.C practicals!

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  11. Lead acetate test is misssing...

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    Replies
    1. This comment has been removed by the author.

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  12. Its clear and very useful

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  13. Not good enough for the ISC students, be universal and neutral against boards

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  14. It is for HSC Students of TN Board.

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  15. I want the ammonium carbonate salt, because it is too puzzling to me.

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  16. I want the ammonium carbonate salt, because it is too puzzling to me.

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  17. u cant get the test of copper readily by passing h2s gas.. you have to make the conc. of acid(hcl) 0.3N in order for sufficient amount release of sulfide ions.. to exceed the solubity product of CuS..

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  18. add pale yellow for potassium

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  19. Being a CBSE 16-17 student, I didn't find this useful! :(

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  20. Really usefull..Nevertheless but should put some notes..thanks

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  21. if you could write the reaction equations....would be better!!!

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  22. Is there any difficulty in testing a mixture of aluminum and zinc ions by ash test

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    Replies
    1. No. Aluminum give Blue colour ash and zinc give green colour ash clearly.

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  23. if we can use sodium sulpide soltion instead of hydrogen sulpide gas.if yes then how we can prepare its solution

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  24. funny particals iam also reading the particals in 10th std

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  25. It's very useful to me sir iam abirami thankyou

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  26. What is the principle behind as test

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  27. Thanks a lot it's very useful to me before the day of board practical once agian thank u

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  28. Send general procedure for+formate
    Sir

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  29. very nice post. Thank you for sharing this post. It is a very useful article. see more - speciality chemicals company in mumbai

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  30. Capital W small w … Capitaal Wuuu smalll wuu……….

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