Identify 2 Basic And 2 Acid Radicals. This practical salt analysis is in the 11th, 12th, and BSC chemistry syllabi. This is a very important practical and also a bit difficult because patience is very important in this practice.
The test of acidic radicals is not as complicated as the testing of alkaline radicals because in alkaline radicals a sequential test has to be done.
Identify 2 Basic And 2 Acid Radicals
There are 6 groups and each group has a group reagent by which precipitate is formed. The formation of precipitate in any group shows the presence of the group.
Identify 2 Basic And 2 Acid Radicals
Acidic Radicals:-Identify 2 Basic And 2 Acid Radicals
For the purpose of analysis, acidic radicals are divided into three groups-
First Group CO3—(Carbonate),NO2—(Nitrite),S—(Sulphide),SO3—(Sulfite),CH3COO–(Acetate),S2O3—(Thio Sulphate)
Second Group NO3–(Nitrate),Cl–(Chloride),Br–(Bromide),I–(Iodide),C2O4—(Oxalate),F–(Flouride),[Fe(CN)6]—-(Ferrocyanide)
Third Group PO4—(Phosphate),SO4—(Sulphate),BO3—(Borate)
Identify 2 Basic And 2 Acid Radicals
Basic Radicals
For the purpose of analysis, Basic radicals are divided into 6 groups-
Zero Group NH4+(Ammonium Ion)|
First Group Ag+(Silver),Pb++(Lead),Hg2++(mercurous )|
Second Group Hg++(Mercuric),Pb++(Lead),Bi+++(Bismuth),Cu++(Copper),Cd++(Cadmium),Sn++(Stanus Tin),Sn++++(Stanic Tin),As+++(Arsenic) And Sb+++(Antimony)
Third Group Fe+++(Ferric iron),Al+++(Aluminium),Cr+++(Chromium)|
Fourth Group Ni++(Nikil),Co++(Cobalt),Zn++(Zink) And Mn++(Maganese)|
Fifth Group Ba++(Barium),Sr++(Strontium) And Ca++(Calcium)|
Sixth Group Mg++(Magnesium)
Identify 2 Basic And 2 Acid Radicals
Acidic Radical Test:-Identify 2 Basic And 2 Acid Radicals
They are Tested like Alkaline radicals by two methods dry and wet tests. Acidic radicals can be estimated by the dry test but their confirmation is done by the wet test.
Wet tests for acidic radicals are not carried out according to a systematic plan, as in the case of basic bases. The solution of the mixture is made to do the wet test. In this, the acidic radicals of the mixture go in the form of sodium salt. A wet test is done in this only.
Method of preparation of soda extract-
Identify 2 Basic And 2 Acid Radicals
Take 1 part mixture with 3 parts solid anhydrous sodium carbonate in a beaker. Add 15-20 ml distilled water to it and boil for 10-15 minutes.
While heating, the volume of the solution should not be less than 10-15ml, so keep adding distilled water as needed after a while. Filter the solution.
Filtered soda is the extract.
Wash the residue with 2 ml of distilled water and mix the wash with the main filtrate.
Theory:-
Identify 2 Basic And 2 Acid Radicals
When the mixture is heated with a concentrated solution of sodium carbonate, amphoteric decomposition takes place and the acidic radicals present in the mixture combine with the sodium salt of Na2CO3 (Na+) to form sodium salt.
These salts are soluble in water, so they go into the filtrate when filtered.
Identify 2 Basic And 2 Acid Radicals
First Group
Dil Acid Test
(Testing For CO3—(Carbonate),NO2—(Nitrite),S—(Sulphide),SO3—(Sulfite),CH3COO–(Acetate),S2O3—(Thio Sulphate)radical )
| radical | experiment | Observation | Result |
| CO3—(Carbonate) | (1.)Taking the mixture in a test tube, dilute HCl or dilute H2SO4 was added.Confirmatory test
(2.)The gas coming out of the test tube was passed through the conducting tube into the lime water. |
Odorless, colorless carbon dioxide gas is released with effervescence.
Lime water turns milky.
|
CO3—can be |
CO3–Confirm
|
| SO3—(Sulfite) | (1)Taking the mixture in a test tube, add dilute HCl or dilute H2SO4 and heat it.Confirmatory Test
(2)A filter paper moistened with acidified potassium dichromate is brought to the mouth of the test tube. |
Colorless, burning sulfur-scented gas
Filter paper turns green.
|
SO3—(Sulfite)can be.
SO3—(Sulfite) Confirm
|
| S—(Sulphide) | (1)Taking the mixture in a test tube, add dilute HCl or dilute H2SO4 and heat it.Confirmatory Test
(2)A filter paper moistened with LeadAcetate is brought to the mouth of the test tube. |
Colorless smells like rotten eggs
Filter paper turns green or brown |
S—(Sulphide)can be.
S—(Sulphide) Confirm |
| NO2—(Nitrite) | (1.)Taking the mixture in a test tube, dilute HCl or dilute H2SO4 was added.Confirmatory Test
(2)A filter paper moistened with potassium iodide and starch is brought to the mouth of the test tube. |
Brown-colored and pungent-smelling gas emerges.
filter paper turns purple or blue
|
NO2—(Nitrite) Can Be
NO2—(Nitrite) Confirm |
| CH3COO–(Acetate) | (1)Taking the mixture in a test tube, add dilute HCl or dilute H2SO4 and heat it.Confirmatory Test
(1)Neutral FeCl3 Sol. is added to the solution (2) Mixture and solid oxalic acid rubbed on the palm in the presence of two drops of water |
smells like vinegar
The color of the solution turns red
smells like vinegar |
CH3COO–(Acetate)Can Be
CH3COO–(Acetate)Confirm |
| S2O3—(Thio Sulphate) | (1)Taking the mixture in a test tube, add dilute HCl or dilute H2SO4 and heat it.Confirmatory Test
(2) 2-3 ml of silver nitrate solution is added to the sodium carbonate extract. |
A colorless gas with the odor of burnt sulfur is evolved. The solution turns white at first and then turns yellow.
A white precipitate is obtained which turns yellow, orange, brown, and finally black. |
S2O3—(Thio Sulphate)
S2O3—(Thio Sulphate) |
Identify 2 Basic And 2 Acid Radicals
Second Group
Identify 2 Basic And 2 Acid Radicals
Conc. Acid Test
NO3–(Nitrate),Cl–(Chloride),Br–(Bromide),I–(Iodide),C2O4—(Oxalate),F–(Flouride),[Fe(CN)6]—-(Ferrocyanide)
Identify 2 Basic And 2 Acid Radicals
| Radical | experiment | Observation | Result |
| NO3–(Nitrate) | (1.)The mixture and concentrated H2SO4 are heated in a test tube.
Confirmatory test (1) Copper shavings are put in the test tube. (2) Ring test is boiled in distilled water and filtered. Mixing fresh ferrous sulfate solution in the filtrate, concentrated H2SO4 is poured slowly along the wall of the test tube
|
Light brown-colored gas with a strong odor is released.
Gas is released in large quantities.
A brown-colored ring is formed at the place where both liquids meet.
|
NO3–(Nitrate)can be |
NO3–(Nitrate)Confirm
|
| Cl–(Chloride)
|
The mixture and concentrated H2SO4 are heated in a test tube.
Confirmatory Test (1) A rod dipped in NH4OH is taken at the mouth of the test tube. (2)MnO2 is added to the test tube and heated. (3) Silver nitrate test – AgNO3 solution is added to distilled water or dilute HNO3 solution or sodium carbonate extract neutralized with dilute HNO3. The white precipitate is dissolved in the NH4OH solution.
The gas is passed through the NaOH solution and acetic acid and lead acetate are added |
A colorless, pungent odorous gas emanating from concentrated HCl.
White dark smoke is formed.
Yellowish-green gas with a strong odor is evolved. A white precipitate is obtained.
are soluble. Red-colored gas is released.
The yellow-colored precipitate is obtained
|
Cl–(Chloride) can be.
Cl–(Chloride) Confirm
Cl–(Chloride) Confirm
Cl–(Chloride) Confirm |
| Br–(Bromide) | The mixture and concentrated H2SO4 are poured into a test tube and heated.Confirmatory Test
The mixture is heated in a test tube with MnO2 and Conc. H2SO4 |
reddish brown gas with a pungent odor
Reddish brown gas is released in excess
|
Br–(Bromide) can be
Br–(Bromide) confirm
|
| I–(Iodide) | The mixture and concentrated H2SO4 are poured into a test tube and heated.Confirmatory Test
put MnO2 in the above test tube
|
Violet vapors are evolved and freeze on the colder parts of the test tube.
purple vapors came fast
|
I–(Iodide) can be
I–(Iodide) confirm
|
| C2O4—(Oxalate) | Take the mixture and concentrated H2SO4 in a test tube and heat it slowly. Burning paper is brought to the mouth of the test tube.Confirmatory TestNeutralize 2ml soda extract with acetic acid and remove CO2 by heating. Add CaCl2 solution to it and wait for 2 minutes. |
Colorless and odorless gas is released.
Paper burns with a blue flame.
White precipitate appears.
|
C2O4—(Oxalate) can be
C2O4—(Oxalate) confirm
|
| F–(Flouride) | The mixture and concentrated H2SO4 are poured into a test tube and heated.Confirmatory Test
Heat the mixture, sand, and concentrated H2SO4 in a dry test tube and bring a glass rod soaked in water to the mouth of the test tube. |
white gas with a pungent odor
white precipitate on a glass rod
|
F–(Flouride) can be
F–(Flouride) confirm
|
| [Fe(CN)6]—-(Ferrocyanide) | The mixture is heated with concentrated H2SO4.Confirmatory Test
Ammonium molybdate is added to the solution with dilute HCl, |
A gas burning with a colorless blue flame is obtained.
a brown precipitate is obtained.
|
[Fe(CN)6]—-(Ferrocyanide) can be
[Fe(CN)6]—-(Ferrocyanide) confirm
|
Identify 2 Basic And 2 Acid Radicals
Third Group
PO4—(Phosphate),SO4—(Sulphate),BO3—(Borate)
| Radical | Experiment | Observation | Result |
| Sulphate SO4— | BaCl2 solution is added to a solution made in HCl to a dilute or concentrated solution of the mixture.
confirmatory test
The precipitate is dissolved in Aqua regia or concentrated HNO3.
|
The thick white precipitate is obtained.
are insoluble. |
Sulphate SO4—can be
Sulphate SO4— Confirm |
| Phosphate PO4— | The mixture is heated with Conc. HNO3. Ammonium molybdate solution is added. let’s cooldown | A yellow precipitate is obtained. | Phosphate PO4— Confirm |
| Borate BO3— | Take the mixture and ethyl alcohol (1 c.c. or 2 c.c) in a porcelain cup and add concentrated H2SO4.The solution is heated by stirring it with a glass rod.
Burning paper is brought in contact with the emanating gas.
|
The gas burns with a green-colored flame. | Borate BO3—Confirm |
Identify 2 Basic And 2 Acid Radicals
Basic Radical Test
Insoluble compounds of basic radicals, such as chlorides, sulfides, hydroxides
and are precipitated in the form of carbonates etc.
All the basic radicals are divided into 6 groups because of their ability to form the above type of compounds.
The properties of the members of each group are similar to each other, that is, they form insoluble compounds with certain specific reagents, which are called group reagents.
Identify 2 Basic And 2 Acid Radicals
| Group | Basic Radical | Group Reagent | Specialty of Group |
| Zero | NH4+ | NaOH | NaOH reaction gives Ammonia salt NH3 |
| First(Silver Group) | Pb2+,Ag+,Hg22+ | Dil HCl | The chlorides of these metals are insoluble in water. The sulfides of these metals are insoluble in dilute HCl. |
| Second(copper-Arsenic Group) | Hg++(Mercuric),Pb++(Lead),Bi+++(Bismuth),Cu++(Copper),Cd++(Cadmium),Sn++(Stanus Tin),Sn++++(Stanic Tin),As+++(Arsenic) And Sb+++(Antimony) | H2S in the presence of dilute HCl | The hydroxides of these metals are insoluble in water. |
| Third Group | Fe+++(Ferric iron),Al+++(Aluminium),Cr+++(Chromium)| | NH4OH in the presence of NH4Cl | The sulfides of these metals are insoluble in ammonium solution. The carbonates of these metals are insoluble in ammonium solution. |
| Fourth Group | Ni++(Nikil),Co++(Cobalt),Zn++(Zink) And Mn++(Maganese)| | H2S in the presence of NH4Cl and NH4OH | |
| Fifth Group | Ba++(Barium),Sr++(Strontium) And Ca++(Calcium)| | (NH4)2CO3 in the presence of NH4Cl and NH4OH | |
| Sixth Group | Mg++(Magnesium) | Na2HPO4 in the presence of NH4Cl,NH4OH and (NH4)2CO3 |
Identify 2 Basic And 2 Acid Radicals
