99 Percentile Qs Bank for JEE MainChemistryGeneral Organic Chemistry
In Lassaigne's test for halogens, it is necessary to remove ' X ' and ' Y ' from the sodium fusion extract, if nitrogen and Sulphur are present. This is done by boiling the extract with ' Z ' . Identify X ,   Y and Z .
Options
- AX = NaNO 3 Y = Na 2 SO 4 Z = conc.   HNO 3
- BX = NaNH 2 Y = NaSH Z = conc.  HCl
- CX = NaNO 2 Y = Na 2 SO 3 Z =  conc.  H 2 SO 4
- DX = NaCN Y = Na 2 S Z =  conc.  HNO 3
Correct answer
D. X = NaCN Y = Na 2 S Z =  conc.  HNO 3
Step-by-step solution
Lassaigne's extract is used for the detection of nitrogen and sulphur. In this the organic compound reacts with the sodium thiocyanate followed by the Fe 3 + cation and formed the [ Fe ( SCN ) ] 2 + complex which is red blood colour. For the test of halogens, it is necessary to remove the sodium cyanide and sodium sulphide. So, the compound X is sodium cyanide and compound Y is sodium sulphide. These can be removed by the nitric acid. NaCN X   +   HNO 3 Z → NaNO 3   +   HCN Na 2 S Y &#