What is the process to prepare sodium extract?
What is the process to prepare sodium extract?
Preparation of Sodium Fusion Extract (Lassaigne’s Extract)
- Take a small piece of dry sodium in a fusion tube.
- Heat the tube slightly on a Bunsen burner so that the sodium melts to a shining globule.
- Add a pinch of the organic compound.
- Heat it slowly to start with so that the compound reacts with sodium metal.
What is the composition of sodium extract if the organic compound contains nitrogen as foreign element?
If nitrogen is present in the organic compound, NaCN is formed in the sodium extract, which also gives white ppt. with silver nitrate solution. If sulphur is present in the organic compound, Na2S is formed in the sodium extract which gives black ppt.
Why is an organic compound fused with sodium metal when preparing the Lassaigne’s extract?
Why an organic compound is fused with sodium metal for preparing Lassaigne’s extract? Ans. When the organic compound is heated with sodium, the elements such as nitrogen, sulphur and halogens, if present in the compound, are converted into sodium salts which are soluble in water.
What is sodium extract?
It is a general test for the detection of halogens, nitrogen and sulphur in an organic compound. The ionic compounds formed during the fusion are extracted in aqueous solution and can be detected by simple chemical tests. The extract is called sodium fusion extract or Lassaigne’s extract.
Why is sodium extract alkaline in nature?
Why is the sodium extract alkaline in nature? Ans. Because the organic compound is fused with sodium metal and then it is extracted with water. The unreacted metal reacts with water and forms an alkaline solution.
Why is HNO3 added before adding agno3 solution for the detection of halogen in organic compound?
Nitric acid decomposes sodium cyanide and sodium halide. else, they precipitate in test and misguide the result. Therefore, dilute nitric acid is added before testing halogens to expel all the gases if evolved.