Molecular formula a chemical formula expressing the number of each element present in a substance without indicating how they are linked. The letter shows what chemical element each atom is. N 2 O 2 NO.
A chemical formula is a way that chemists describe a molecule.
Sometimes the formula shows how the atoms are linked and sometimes the formula shows how the atoms are arranged in space. Chemistry a chemical formula showing the composition and structure of a molecule. An expression which states the number and type of atoms present in a molecule of a substance. Molecular formula a chemical formula expressing the number of each element present in a substance without indicating how they are linked.