A student has been given a compound “x” of molecular formula – C₆H₇N. ‘x’ is sparingly soluble in water. However, on addition of dilute mineral acid , ‘x’ becomes soluble in water. ‘x’ when treated with CHCl₃ and KOH (alc.) ‘y’ is produced. ‘y’ has a specific unpleasant smell. On treatment with benzenesulphonyl chloride, ‘x’ gives a compound ‘z’ which is soluble in alkali. The number of different “H” atoms present in ‘z’ is:-