Tarnish is produced by a redox reaction that occurs when a metal reacts with a nonmetallic compound. The green tarnish on a copper penny might be
produced by a reaction between copper and hydrogen sulfide. What occurs
during this reaction?
A. Hydrogen sulfide acts as an acid, and copper acts as a base.
B. Copper atoms gain electrons from sulfur atoms.
C. A double-replacement reaction takes place.
D. Copper atoms lose electrons to sulfur atoms.