What is the percentage by mass of copper in copper in copper (l) oxide (CU2O)? [O = 16; CU =64] By: Sunday|Published on: Aug 22|Categories: Chemistry WAEC| 0 comments A. 88.9% B. 80.0% C. 66.7% D. 20.0% E. 11.1% Correct Answer: Option A – 88.9% Users Also Read These:118.8cm² surface of the copper cathode of a…What mass of copper in gram would be deposited by a…Which of the following elements would displace…A piece of copper of mass 30g loses 60J of heat…Calculate the mass of the copper deposited during…SEE ALSO A few drops of concentrated HNO3 is added to an unknown solution and boiled for a while. If this produces a brown solution, the cation present is likely to be?