| Element | Atomic Weight | Electrons |
| Hydrogen (H) | 1 | 1 |
| Carbon (C) | 12 | 6 |
| Nitrogen (N) | 14 | 7 |
| Oxygen (O) | 16 | 8 |
| Fluorine (F) | 19 | 9 |
| Sulfur (S) | 32 | 16 |
| Chlorine (Cl) | 35 | 17 |
| Bromine (Br) | 80 | 35 |
Atomic species are rare in the atmosphere
as they tend to react with other atoms or molecules.
Some common compounds include:
| Compound | Names |
| O2 | Oh-Two (literal name)
Oxygen (common name) Molecular oxygen (formal name) Dioxygen (strict nomenclature) |
| N2O | En-two-oh (literal name)
Laughing gas (popular name) Nitrous oxide (formal name) Dinitrogen monoxide (strict nomenclature) |
| NH3 | En-aitch-three (literal name)
Ammonia (common name) Ammonia (formal name) Nitrogen trihydride (strict nomenclature) |
A chemical reaction is a quantitative statement describing the interaction between two materials (or compounds or species), the reactants, that leads to the generation of different materials, the products. Atoms are not created or destroyed.