Answer:
Metal
Step-by-step explanation:
An atom in general is composed of a positive charged core with electrons that move around in quantized orbits. The electrons present in the outermost orbits are called valence electrons and it is these electrons that generally participate in chemical interactions. The valence electrons are bound to the nucleus by electrostatic forces of attraction. However, when an appropriate amount of energy is supplied these electrons can be released.
Metals are the elements that lose valence electrons easily and form positively charged ions called cations. The energy supplied is termed as the ionization energy. For example, sodium (Na) is an alkali earth metal with a valence electron configuration of 3s1. The one electron present in the outer 3s orbital can be ionized to form Na+ ion.