These are the smallest particle in a chemical element or compound that has the chemical properties of that element or compound. Molecules are made up of atoms that are held together by chemical bonds.
These are lasting attraction forces between atoms that enable the formation of chemical compounds. They're like the glue holding your cake ingredients together!
These are pure substances consisting only of atoms that all have the same numbers of protons in their atomic nuclei. Elements can't be broken down into simpler substances by any ordinary chemical means. They're like individual ingredients (flour, sugar) in your cake recipe.