Element symbols and chemical formulas In the later chemical formula, like H20, it has four meanings (macro and micro angles), but some element symbols also have four meanings, and some do not. How can we distinguish them

Element symbols and chemical formulas In the later chemical formula, like H20, it has four meanings (macro and micro angles), but some element symbols also have four meanings, and some do not. How can we distinguish them

The meaning of element symbol:
1: Macro perspective: represents an element
2: Micro angle: can represent an atom
*Special case: for a substance directly composed of atoms, the element symbol can also indicate a substance (including all metals, rare gases, C, Si, s, P). If the element is preceded by a number, it only indicates the microscopic meaning
It has two meanings: H, N, O, F and CL
There are three meanings: 1. Noble gases: he, NE, AR, Xe, RN
2. Metal elements: Li, be, Na, Mg, Al, K, CA, Fe, Cu, Zn
Special elements: C, Si, P, s