How many of the following statements are correct about the froth flotation method.
a) This method has been in use for removing gangue from sulphide ore.
b) Pine oil enhance non-wettability of the mineral particles
c) Aniline stabilizes the froth.
d) Sodium cyanide selectively prevents lead sulphide from coming to the froth but allows zinc sulphide to come with the froth
e) Fatty acids act as collectors
f) Cresols act as stabilizers of froth