Which of the following is a chemical property of iron.
Iron has a hardness of 4-5.
Iron rusts when exposed to water and oxygen.
The melting point of iron is 1536 degrees Celsius.
The boiling point of iron is 3000 degrees Celsius.
The correct answer is: B) Iron rusts when exposed to water and oxygen, because it results in a chemical change of the iron, becoming iron oxide. The other changes are all physical.