(P) Making soluble salts using an insoluble base

• 1)You need to pick the right acid and insoluble base, such as an insoluble metal oxide, hydroxide or carbonate. E.g. if you want to make copper chloride, you could mix hydrochloric acid and copper oxide (you could also react the acid with a metal:

  CuO(s) + 2HCl(aq) -> CuCl2(aq) + H2O
• 2) Gently warm the dilute acid using a Bunsen burner, then turn off the Bunsen burner
• 3) Add the insoluble base to the acid a bit at a time, until no more reacts (i.e. the base is in excess). You'll know when all the acid has been neutralised because, even after stirring, the excess solid will just sink to the bottom of the flask

  
• 4) Then filter out the excess solid to get the salty solution

  
• 5) To get pure, solid crystals of the salt, gently heat the solution using a water bath or an electric heater to evaporate some of the water (to make it more concentrated) and then stop heating it and leave the solution to cool. Crystals of the salt should form, which can be filtered out of the solution and then dried. This is called crystallisation