CUSO4係acidic定alkaline

copper ii sulphate solution is acidic.
it is formed from a strong acid and a weak alkaline.
so the product is acidic.
the fact is that the strong sulphuric acid is completely
ionized in water, and the sulphate ion will not react with
water to form the acid again.
but the copper ii ion will react with water to form
copper ii hydroxide and hydrogen ion.
so the solution is acidic.
furthermore, the solubility product of copper ii hydroxide
is not exceeded, so there is no any pale blue ppt of
copper ii hydroxide formed.

2008-06-25 18:48:26 補充：
of course not.
potassium sulphate and sodium sulphate is neutral.
salt of strong acid and strong alkaline is neutral.