Final answer:
Group 8A (18) elements are classified as nonmetals known as noble or inert gases, characterized by their lack of reactivity and filled valence electron shells.
Step-by-step explanation:
Elements located in Group 8A (18) of the periodic table are known as the noble gases or inert gases.
These elements are characterized by their lack of reactivity under normal conditions and are classified as nonmetals. The noble gases include helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and the radioactive radon (Rn).
These gases are colorless, odorless, and have very low chemical reactivity due to their filled valence electron shells.Based on its location in the periodic table, indium is classified as a metal.
Indium is located in Group 13 (3A) of the periodic table, which is composed of metals. Metals are typically malleable, ductile, and good conductors of electricity.