It's attraction for electrons
The valence electrons
atomic mass
The number of electrons determines an element's position.
The elements that compose it and the arrangement of its atoms
The number of electrons in an element determines its chemical properties and behavior. Specifically, it influences how an element will bond with other elements to form compounds and determines its reactivity.
similarity of electronegativity of the 2 elements
Electrons.
Elements in same column have same number of outermost electrons. It determines chemical properties.
Because different elements have different numbers of protons, which determines the atomic number.
their boiling point and melting point.....etc.
The atomic weight, or the number of protons.
The amount of electrons in each element.