Experiment 3
Experiment 3
AIM:- To detect the presence of unknown elements(like N,S,P,X) in a given organic compound.
AIM:- To detect the presence of unknown elements(like N,S,P,X) in a given organic compound.
MATERIAL REQUIRED:- given organic compound, Na piece ,ferrous sulphate, dil.sulphuric acid, dil.acetic acid, lead acetate, dil.nitric acid , silver nitrate , ignition tubes, tongs, bunsen burner, wire gauge, china dish, filter paper, funnel, glass rod, test tubes.
MATERIAL REQUIRED:- given organic compound, Na piece ,ferrous sulphate, dil.sulphuric acid, dil.acetic acid, lead acetate, dil.nitric acid , silver nitrate , ignition tubes, tongs, bunsen burner, wire gauge, china dish, filter paper, funnel, glass rod, test tubes.
THEORY:-The detection of extra elements in organic compounds is crucial in its investigation. Carbon is included in all organic molecules. Hydrogen is also found in most organic molecules (the few exceptions are the compounds such as CCl₄, CS₂, etc.). Other elements included in organic molecules include oxygen, nitrogen, sulfur, and halogens, in addition to carbon and hydrogen. Because virtually all organic substances include carbon and hydrogen, procedures to identify them are frequently unnecessary, and their existence may be presumed without testing. The tests for detecting nitrogen, sulfur, and halogens will be discussed here.
THEORY:-The detection of extra elements in organic compounds is crucial in its investigation. Carbon is included in all organic molecules. Hydrogen is also found in most organic molecules (the few exceptions are the compounds such as CCl₄, CS₂, etc.). Other elements included in organic molecules include oxygen, nitrogen, sulfur, and halogens, in addition to carbon and hydrogen. Because virtually all organic substances include carbon and hydrogen, procedures to identify them are frequently unnecessary, and their existence may be presumed without testing. The tests for detecting nitrogen, sulfur, and halogens will be discussed here.
What is the Lassaigne’s Test, and how does it work?
What is the Lassaigne’s Test, and how does it work?
Lassaigne’s test can identify nitrogen, sulfur, and halogens organic molecules. A little bit of Na metal is heated with the organic compound in a fusion tube.
Lassaigne’s test can identify nitrogen, sulfur, and halogens organic molecules. A little bit of Na metal is heated with the organic compound in a fusion tube.
The idea is that Na changes all of the elements present into ionic form.
The idea is that Na changes all of the elements present into ionic form.
Na + C + N → NaCN
Na + C + N → NaCN
2Na + S → Na₂S
2Na + S → Na₂S
Na + X → NaX ( X= Cl, Br, or I)
Na + X → NaX ( X= Cl, Br, or I)
By boiling the fused mixture with distilled water, the produced ionic salts are removed. Sodium fusion extract is what it’s called.
By boiling the fused mixture with distilled water, the produced ionic salts are removed. Sodium fusion extract is what it’s called.
Preparation of lessaigne extract:-
Preparation of lessaigne extract:-
In a fusion tube, place a little piece of dry sodium. Warm the line until it melts into a gleaming globule. A pinch of the organic substance should be added. First, heat it slowly to allow the chemical to react with sodium metal. Now bring it to a high temperature. Plunge the red hot tube into distilled water in a porcelain dish. Using a glass rod, crush the ingredients and bring to a boil. Filtration is used to remove the insoluble materials. Lassaigne’s extract is the name given to the filtrate.
In a fusion tube, place a little piece of dry sodium. Warm the line until it melts into a gleaming globule. A pinch of the organic substance should be added. First, heat it slowly to allow the chemical to react with sodium metal. Now bring it to a high temperature. Plunge the red hot tube into distilled water in a porcelain dish. Using a glass rod, crush the ingredients and bring to a boil. Filtration is used to remove the insoluble materials. Lassaigne’s extract is the name given to the filtrate.
Using extract for detecting presence of unknown elements:-
Using extract for detecting presence of unknown elements:-
Sulphur testing
Sulphur testing
Aim:-to detect presence of sulphur in given organic compound.
Aim:-to detect presence of sulphur in given organic compound.
Materials required : lassaigne extract, test tubes, tongs, dil.acetic acid, lead acetate.
Materials required : lassaigne extract, test tubes, tongs, dil.acetic acid, lead acetate.
Procedure:
Procedure:
take 1ml extract in test tube.
take 1ml extract in test tube.
add 1ml dil acetic acid for acidification.
add 1ml dil acetic acid for acidification.
now add lead acetate in the test tube.
now add lead acetate in the test tube.
Observation:-
Observation:-
no change in test tube.
no change in test tube.
Result:-
Result:-
given organic compound does not contain sulphur as their is no formation of black ppt.
given organic compound does not contain sulphur as their is no formation of black ppt.
Halogens testing
Halogens testing
Aim :- to detect presence of halogen in given organic compound.
Aim :- to detect presence of halogen in given organic compound.
Materials required:- lassaigne extract, test tubes, tongs, dil.nitric acid, silver nitrate.
Materials required:- lassaigne extract, test tubes, tongs, dil.nitric acid, silver nitrate.
Procedure:-
Procedure:-
take 1ml lassaigne extract in a test tube.
take 1ml lassaigne extract in a test tube.
add 1 ml dil.nitric acid in a test tube.
add 1 ml dil.nitric acid in a test tube.
now add little silver nitrate in the test tube.
now add little silver nitrate in the test tube.
Observation:-
Observation:-
no change in the test tube.
no change in the test tube.
Result:- no change in test tube assures absence of halogen.
Result:- no change in test tube assures absence of halogen.
Nitrogen testing
Nitrogen testing
Aim:-to detect presence of nitrogen in given organic compound.
Aim:-to detect presence of nitrogen in given organic compound.
Materials required:- lassaigne extract, test tube, tongs, dil.sulphuric acid, ferrous sulphate.
Materials required:- lassaigne extract, test tube, tongs, dil.sulphuric acid, ferrous sulphate.
Procedure:-
Procedure:-
take 1 ml lassaigne extract in a test tube.
take 1 ml lassaigne extract in a test tube.
add one spatula ferrous sulphate in the test tube.
add one spatula ferrous sulphate in the test tube.
now, acidified the extract with dilute H₂SO₄ and heated it shortly.
now, acidified the extract with dilute H₂SO₄ and heated it shortly.
let it be cool and observe the change of colour.
let it be cool and observe the change of colour.
Observation:-
Observation:-
The appearance of Prussian blue colour.
The appearance of Prussian blue colour.
Result:- prussian blue colour indicates presence of nitrogen
Result:- prussian blue colour indicates presence of nitrogen
PRECAUTIONS:-
PRECAUTIONS:-
Here are some precautions to consider when performing the Lassaigne's sodium fusion test:
Here are some precautions to consider when performing the Lassaigne's sodium fusion test:
1. Safety: Wear appropriate personal protective equipment, such as gloves and goggles, to protect yourself from any potential hazards.
1. Safety: Wear appropriate personal protective equipment, such as gloves and goggles, to protect yourself from any potential hazards.
2. Handling sodium: Sodium is a highly reactive metal that reacts violently with water. Handle sodium with caution, using dry forceps or spatula, and keep it away from moisture.
2. Handling sodium: Sodium is a highly reactive metal that reacts violently with water. Handle sodium with caution, using dry forceps or spatula, and keep it away from moisture.
3. Fusion process: Carefully add a small amount of the organic compound to the fusion tube, followed by a small piece of sodium metal. Avoid adding excessive amounts of sodium, as it may lead to violent reactions.
3. Fusion process: Carefully add a small amount of the organic compound to the fusion tube, followed by a small piece of sodium metal. Avoid adding excessive amounts of sodium, as it may lead to violent reactions.
4. Heating: Heat the fusion tube gently and gradually to avoid any sudden reactions or splattering. Use a Bunsen burner or a heating mantle for controlled heating.
4. Heating: Heat the fusion tube gently and gradually to avoid any sudden reactions or splattering. Use a Bunsen burner or a heating mantle for controlled heating.
Pictures related to Experiment
Pictures related to Experiment