Often we hear that water is H2O. This is the chemical formula for water molecule. This means that each molecule of water has two hydrogen atoms combined with one oxygen atom. A chemical formula is a symbolic representation of one molecule of an element or a compound. It provides information about the elements present in the molecule and the number of atoms of each element. Can you guess the types of atoms and number of each of the atoms in NaCl, which is the chemical formula for cooking salt?
The chemical formula tells us the types of atoms and the number of each type of atom in one molecule of substance
Here are some examples of chemical formula
1 atom of Sodium and 1 atom of chlorine
1 atom of Nitrogen and 3 atoms of Hydrogen
6 carbon atoms, 12 Hydrogen atoms 6 oxygen atoms
compounds and their chemical formula