Question

What property of metals is reactivity

Answer 1

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 2

The reactivity of metals are determined by the number of electrons on the outermost shell