Categorization of the First Twenty Elements
| Metals | Semi-metals | Non-metals |
|---|---|---|
| Lithium (Li) | Boron (B) | Hydrogen (H) |
| Beryllium (Be) | Silicon (Si) | Helium (He) |
| Sodium (Na) | Carbon (C) | |
| Magnesium (Mg) | Nitrogen (N) | |
| Aluminium (Al) | Oxygen (O) | |
| Potassium (K) | Fluorine (F) | |
| Calcium (Ca) | Neon (Ne) | |
| Phosphorus (P) | ||
| Sulphur (S) | ||
| Chlorine (Cl) | ||
| Argon (Ar) |
Elements on the left side of the periodic table are metals. Silicon and Boron are semi metals (have some properties of both metals and non-metals). Elements on the right side of the periodic table are non-metals.