Honda and Toyota Both Sell Hybrid Cars That Have Engines

Multiple Choice

Honda and Toyota both sell hybrid cars that have engines that can run on either gasoline or electricity stored in a battery. The advantage of hybrid cars is simple: Totally electric cars need batteries that weigh almost as much as the vehicle! It isn't surprising that a high priority is the search for better batteries. Barium ferrate (BaFeO₄) is being tested for use in batteries. Use the positions of barium and oxygen in the periodic table to predict the oxidation state of the iron atom in this compound.

A) +2
B) +3
C) +4
D) +6
E) +8