Question

18/22 an atom’s valence electron shell: is filled when it has three electrons determines its chemical reactivity is filled with positively charged particles measures the size of the atom

Explanation:

The valence - electron shell contains the electrons involved in chemical bonding. The number of valence electrons determines how an atom will react chemically with other atoms. A full valence shell makes an atom stable, and the tendency to gain, lose, or share electrons to achieve a full valence shell drives chemical reactivity.

Answer:

B. determines its chemical reactivity