✔ 最佳答案
其實有反應的, 只不過憑肉眼好難睇得到.....
當Copper(II) chloride react with Magnesium sulphate, Copper(II) sulphate and magnesium chloride are formed, since both of them are soluble in water, so no observable change is detected:
CuCl2 + MgSO4 <--> CuSO4 + MgCl2
Anyway, The reaction will be reversible when two product are all soluble in water,
for example, sodium chloride and potassium nitrate will react to form sodium nitrate and potassium chloride, which are all soluble in water.
When one of the product is insoluble in water, the reaction will flows on only one direction. For example, silver nitrate and sodium chloride will react to form silver chloride and sodium nitrate, since silver chloride is insoluble in water, the reaction can not go back anymore, hence, the reaction is:
AgNO3 + NaCl --> AgCl(s) + NaNO3