Molisch's Test : This is a general test for carbohydrates. One or two drops of alcoholic solution of $$\alpha $$-naphthol is added to $$2$$ ml glucose solution. $$1$$ ml of conc. $${H_2}S{O_4}$$ solution is added carefully along the sides of the test-tube. The formation of a violet ring at the junction of two liquids confirms the presence of a carbohydrare or sugar.