Question

1. the elements in group 2 have similar chemical properties because each atom of these elements has the same - atomic number mass number number of valence electrons number of electron shells clear all

Explanation:

The chemical properties of elements are mainly determined by the number of valence - electrons. Elements in the same group of the periodic table have the same number of valence electrons. Group 2 elements all have 2 valence electrons, which gives them similar chemical reactivity patterns. Atomic number, mass number, and number of electron shells vary among elements in the same group.

Answer:

C. Number of valence electrons