<u><em>Answer:</em></u>
- Correct option is D. Family 18
<u><em>Explanation.</em></u>
The elements of group 18 of periodic table are called as noble gases. They are stable because they have complete valence shell electrons. So there octet rule is satisfied.
The elements of noble gases are
Molecules are made up by chemically bonding two or more atoms of the same element or different elements, they don’t have charge, and the atoms are bonded by covalent bonds. <span>Lattices have a three- dimensional ordered arrangement of basic units (that can be an atom, molecule or an ion). Lattices are crystalline structures with these repeated basic units. When ions joined with ionic bonds, they form ionic crystals. The formula unit tells us that aluminium hydroxide has a crystal structure made from molecules. </span>
A substance that contains two or more kinds of atoms is a molecule.
