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:
I am not 100% sure but I think it is 26.981538
Explanation:
Clouds I believe because hydro means water and clouds are made of water