Chemical Bonds: How Atoms Connect

When atoms join together, they form different types of bonds depending on what elements are involved. Let's look at the three main ways atoms can bond.

Ionic bonding happens when a metal reacts with a non-metal. The metal atoms transfer electrons to the non-metal atoms. This leaves the metal with a positive charge (called a cation) and gives the non-metal a negative charge (an anion). These opposite charges create a strong electrostatic attraction that holds the atoms together.

Covalent bonding occurs between two non-metal atoms. Instead of transferring electrons, these atoms share pairs of electrons between them. These bonds are very strong and require lots of energy to break. Interestingly, while the bonds between atoms in a molecule are strong, the forces between separate molecules are often weak. This explains why many covalently bonded substances have low melting and boiling points.

Metallic bonding forms between metals. In this type of bond, positive metal ions arrange themselves in a regular pattern called a lattice. The outer electrons from these metal atoms become "delocalised" - they're free to move throughout the structure. The attraction between these free-moving electrons and the positive ions creates the metallic bond.

Remember this! You can predict what type of bond will form by looking at the elements involved: metal + non-metal = ionic bond; non-metal + non-metal = covalent bond; metal + metal = metallic bond.