What kind of bond holds together atoms within a molecule?

Explanation: There are two types of bonds that atoms undergo in order to form molecules: covalent and ionic. When atoms of different elements bond, a compound is formed. Covalent bonding occurs when atoms share electrons to form pairs in their outer orbitals. Carbon dioxide (CO2) is an example of a compound that uses covalent bonding. A carbon atom has only four electrons in its outer shell, and an oxygen atom has six. So, one carbon atom shares electrons with two oxygen atoms, creating eight electrons in the outer shell of each atom. This makes a stable compound.

In ionic bonding, electrons are transferred to make stable compounds. Table salt (NaCl) is an example of a compound using ionic bonding. Sodium (Na) has one electron in its outer shell, and chlorine (Cl) has seven. Sodium loses its electron and becomes a positively charged ion, while chlorine gains an electron and becomes negatively charged. The two atoms are attracted and they form salt, an ionic compound.