Fill in the blanks in this concept map to help you tie together the key concepts concerning elements, atoms, and molecules.

Atoms are the fundamental building blocks of matter, consisting of protons, neutrons, and electrons. The atomic number, which is the number of protons in the nucleus, defines each element. Atoms can be positively charged (cations), negatively charged (anions), or neutral, depending on the balance of protons and electrons.

Chemical bonds are the forces that hold atoms together in molecules. They can be formed through the transfer of electrons (ionic bonds) or the sharing of electrons (covalent bonds). The nature of these bonds influences the properties of the resulting compounds, such as polarity and reactivity.

Ionic bonds occur when electrons are transferred from one atom to another, resulting in the formation of charged ions that attract each other. Covalent bonds involve the sharing of electrons between atoms, which can be equal (nonpolar covalent bonds) or unequal (polar covalent bonds), affecting the molecule's polarity and interactions with other substances.