In nuclear symbol notation, the information written as a subscript to the lower left of the elemental symbol is the atomic number. The atomic number represents the number of protons in the nucleus of an atom. It is a unique identifier for each element on the periodic table.
For example, let's take the element carbon with the symbol "C." In nuclear symbol notation, the atomic number for carbon (C) is written as a subscript to the lower left of the elemental symbol. Carbon has an atomic number of 6, indicating that it has 6 protons in its nucleus.
Therefore, when you see an elemental symbol with a subscript number written to the lower left of it in nuclear symbol notation, that number represents the atomic number of the element.
