what do elements and compounds have in common?

Elements and compounds are both types of substances that make up all matter. They are both made up of atoms, but the difference lies in how those atoms are arranged. Elements consist of only one type of atom, while compounds consist of two or more different types of atoms chemically bonded together. Both elements and compounds have specific properties and can undergo chemical reactions.

choose one of these:

they can be chemically broken down into simpler substances.
they are both composed of one type of atom.
they are both pure substances.
they are both homogeneous mixtures.

They can be chemically broken down into simpler substances.