C2 - Bonding, Structure and the Properties of Matter

What are the three types of chemical bonding?

Ionic, covalent, and metallic.

What type of elements form ionic bonds?

Metals and non-metals.

How are ionic bonds formed?

Metal atoms lose electrons; non-metals gain them, forming oppositely charged ions.

What type of structure do ionic compounds form?

Giant ionic lattice

What are the properties of ionic compounds?

High melting points, conduct electricity when molten or in solution.

What type of elements form covalent bonds?

Two non-metals.

What happens in a covalent bond?

Atoms share pairs of electrons.

Give examples of simple covalent molecules.

H₂O, CO₂, CH₄, O₂.

What are the properties of simple covalent substances?

Low melting points and don’t conduct electricity

What is a giant covalent structure?

A large network of atoms covalently bonded (e.g. diamond, graphite, silicon dioxide)

What are the properties of diamond?

Hard, high melting point, doesn’t conduct electricity.

What are the properties of graphite?

Soft, layers slide, conducts electricity (delocalised electrons).

What are fullerenes?

Molecules of carbon arranged in hollow spheres or tubes.

What are metallic bonds?

Attraction between positive metal ions and delocalised electrons.

Why do metals conduct electricity?

Delocalised electrons can move through the structure.

Why are alloys harder than pure metals?

Different-sized atoms distort layers, making them harder to slide.