Copper(l) sulfide can react with oxygen to produce copper metal by the reaction cu2s + o2 => 2cu + so2. if 5.00 g of cu2s is used, then what is the theoretical yield of cu?
a. 10.0 g
b. 1.99 g
c. 1.00 g
d. 5.00 g
e. 3.99 g