The reactivity of a metal is determined by these things.
Firstly, the number of electrons in the outer shell; the fewer the number of electrons in the outer shell, the more reactive the metal.
The number of electron shells also affects reactivity, the more electron shells there are, the more reactive the metal.
Answer:
18 electrons
Explanation:
Note: The third energy level can actually hold up to 18 electrons, so it is not really filled when it has 8 electrons in it.
I would say A. Friction because it is the act of two things rubbing together.
Ex. Trying to make fire
