The student's lab manual says to mix some of his Na2CO3 solution with an aqueous solution of copper (II) sulfate (CuSO4)

What evidence of a chemical reaction would he expect to see? Explain your answer.

If there is a reaction, the most obvious evidence is a color change.

CuSO4 in water is an indescribable blue. In fact it is nicknamed bluestone.

If it reacts to become CuCO3 the color goes to green.

A second piece of evidence is that the CuCO3 is insoluble in a water solution. It will form a precipitate. CuSO4 is very soluble so not only will the color disappear it will be a green solid on the bottom of the container.