2. ----------- to remove the unreacted copper oxide 3. Heat the solution until it is -------------------4. ------------ the solution to form ---------------coloured crytsal of copper

It seems like you're asking for steps in a chemistry experiment, but the question is incomplete. Here's a possible completion based on common procedures:

2. Use a filtration method to remove the unreacted copper oxide. This can be done by pouring the mixture through a filter paper set in a funnel. The copper oxide will remain on the filter paper while the solution passes through.
3. Heat the solution until it is nearly boiling. This can be done using a Bunsen burner or a hot plate. Be careful not to let the solution boil over.
4. Allow the solution to cool and then evaporate to form blue-coloured crystals of copper sulfate. This can take several hours to a few days, depending on the amount of solution and the temperature of the room. The blue crystals are copper sulfate pentahydrate, a common form of copper sulfate.