making soluble salts (topic 4)

How do you make a soluble salt

1) place 40cm³ of dilute sulfuric acid in a beaker and gently heat it with a Bunsen burner. (Then turn it off)

2) using a spatula add small amounts of copper oxide to the beaker and stir it with a glass rod

3) keep adding the copper oxide until it’s in excess to show the reaction has finished

4) filter out the excess copper oxide using filter paper and a filter tunnel over a conical flask to get the salt solution

5) then pour contents of the conical flask into the evaporating basin and evaporate some of the water using a water bath and Bunsen burner

6) stop heating solution and leave it to cool for 24 hours- crystals of salt should start to form which can be filtered out and dried

What’s an observation you can make to show that the zinc oxide is in excess

Zinc oxide solid remaining

Why is excess zinc oxide used rather than excess hydrochloric acid

Zinc oxide can be filtered off

What other compound could add to the hydrochloric acid to produce zinc chloride

Zinc hydroxide or zinc carbonate

How can you obtain crystals of zinc chloride from a solution of zinc chloride

Heat solution to evaporate some of the water then leave solution to cool for 24 hours