Add about 0.50 gram of magnesium turnings to the blue solution
from Part F. (NOTE: Magnesium sulfate solution is colorless and thus the disappearance
of the blue color from the solution shows that all the copper(II) ions
have been displaced from solution. The complete dissolution of the magnesium is
indicated by a uniformly copper-colored (reddish-brown) precipitate and the absence
of bubbles of hydrogen being evolved.)