I. PRELIMINARY TESTS
S. No.
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EXPERIMENT
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OBSERVATION
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INFERENCE
| |
1
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SOLUBILITY
A little of the salt is shaken with water.
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1) Soluble
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1) May be Sulphate, Nitrate, Chloride or Ammonium Carbonate.
| |
2) Insoluble
|
2) May be Carbonate or Sulphide.
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2
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ACTION OF HEAT:
A small amount of the salt is heated gently in a dry test tube.
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1) Colourless, odourless gas turning Lime water milky.
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1) May be Carbonate.
| |
2) Decripitation occurs with evolution of reddish brown gas.
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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.
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3) May be Ammonium.
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4) The white salt turns yellow on heating.
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4) May be Zinc.
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5) No characteristic change.
|
5) Absence of Carbonate, Nitrate, Ammonium and Zinc.
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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.
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1) Presence of Copper.
| |
2) Brick red flame.
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2) Presence of Calcium.
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3) Grassy green flame.
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3) Presence of Barium.
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4) No characteristic coloured flame.
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4) Absence of Copper, Calcium and Barium.
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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.
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1) Presence of Zinc.
| |
2) Blue ash.
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2) Presence of Aluminium.
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3) Pink ash.
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3) Presence of Magnesium.
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4) No characteristic coloured ash.
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4) Absence of Zinc, Aluminium and Magnesium.
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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.
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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.
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1) Chloride is confirmed.
| |
2) No Red orange vapours.
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2) Absence of chloride.
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8
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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.
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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.
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2) Absence of Sulphate
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11
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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.
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2) Presence of Sulphide.
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3) No precipitate.
|
3) Absence of chloride/ sulphide.
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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)
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14. GROUP IDENTIFICATION
S. No
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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).
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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.
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1) Presence of Fourth Group (Zinc).
|
2) No characteristic precipitate.
|
2) Absence of Fourth Group (Zinc).
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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).
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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.
|
RESULT
The given simple salt contains
1. Basic Radical : __________________
2. Acid Radical : __________________
The given simple salt is : ____________________________________
The given simple salt is : ____________________________________
