When you expose a wet iron nail (fe) to the oxygen in air (o2), you will notice that rust, or iron oxide (fe3o4), forms on its surface. which of the following statements is true?

a. the elements iron in the nail and oxygen from the air combine to form the compound rust.

b. the compounds iron in the nail and oxygen from the air combine to form the element rust.

c. the elements rust in the nail and oxygen from the water combine to form the compound iron.

d. the elements iron in the nail and oxygen combine to form the mixture rust.

answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e

3 1/4 %

explanation: