What is the chemistry of Lassaigne’s test?

Question

What is the chemistry of Lassaigne’s test?, Lassaigne's test is a method for the detection of the presence of hydrogen ions (H + ) in a given substance. It involves the reaction of the test substance with sodium metal [NA] to form sodium hydride (NaH), which is then treated with water (H 2 O) to produce hydrogen gas (H 2 ). The evolved hydrogen gas is confirmed using a gas test., Lassaigne's test is a qualitative test used to detect the presence of halogens (chlorine, bromine, and iodine) and nitrogen in organic compounds. The test involves fusing the organic compound with sodium metal [NA] to form sodium cyanide (NaCN) and sodium halides (NaX), where X represents a halogen. The fused mass is then dissolved in water, and the resulting solution is acidified with dilute nitric acid (HNO 3 ) to liberate the respective halogen acids (HX). These liberated halogen acids are identified using specific chemical tests., Lassaigne's test is a procedure for determining the presence of metals in a given sample. It involves heating the sample with sodium metal [NA] to form sodium compounds of the metals present. The resulting mixture is then extracted with water to dissolve the sodium compounds. The aqueous solution is acidified with dilute sulphuric acid (H 2 SO 4 ) to precipitate the metal sulfides, which can be identified by their characteristic colours., Lassaigne's test is a method for determining the presence of carbonate ions (CO 3 2- ) in a given substance. It involves the reaction of the test substance with sodium metal [NA] to form sodium carbonate (Na 2 CO 3 ). The resulting sodium carbonate is then acidified with hydrochloric acid (HCl) to produce carbon dioxide gas (CO 2 ), which is confirmed using a gas test.

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Correct Option is : (B) Lassaigne's test is a qualitative test used to detect the presence of halogens (chlorine, bromine, and iodine) and nitrogen in organic compounds. The test involves fusing the organic compound with sodium metal [NA] to form sodium cyanide (NaCN) and sodium halides (NaX), where X represents a halogen. The fused mass is then dissolved in water, and the resulting solution is acidified with dilute nitric acid (HNO 3 ) to liberate the respective halogen acids (HX). These liberated halogen acids are identified using specific chemical tests.

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