Molecules and Atomicity
A molecule is defined as the smallest unit of a compound that contains the chemical properties of the compound.
- The atomicity of an element is the number of atoms in one molecule of the element.
- For e.g:- Hydrogen, nitrogen, oxygen, chlorine, iodine, bromine all have two atoms in each of their molecules. So, the atomicity of hydrogen, nitrogen, oxygen, chlorine, iodine, bromine is two each.
Structure of atom
- Atom is made of three particles; electron, proton and neutron.
- The centre of the atom is called the nucleus. The nucleus of an atom contains the whole mass of an atom.
- Electrons in an atom are arranged in shells/orbitals.
Valency
Valence electrons are those electrons which are present in the outermost orbit of the atom.
- The capacity of an atom to lose, gain or share valence electrons in order to complete its octet determines the valency of the atom.