Among the following, the essential amino acid is :

A solution containing a group-IV cation gives a precipitate on passing H₂S. A solution of this precipitate in dil.HCl produces a white precipitate with NaOH solution and bluish-white precipitate with basic potassium ferrocyanide. The cation is :

A mixture containing the following four compounds is extracted with $$1M$$ $$HCl.$$ The compound that goes to aqueous layer is :

Which of the following statements is not true about partition chromatography?