how can you make soluble salts with an insoluble base?
1) you need to pick the right acid, plus an insoluble base such as an insoluble hydroxide, metal oxide or carbonate
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 salt 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
