1. Tiffany's class did an experiment to prepare a compound by reacting copper and sulfur. The following is the account of Tiffany's experiment. I weighed some coppet powder and added excess sulfur powder to it. After mixing, a yellow-brown mixture was formed. I heated the mixture in a test tube. It glowed red-hot. A blue-grey solid was formed. I removed the excess sulfur with xylene and obtained the blue-grey solid left behind. (a) Tiffany has left out the details of how she removed the excess sulfur. Describe the procedure she should have used. (Hint: Only sulfur is soluble in xylene.)