2. Reactivity Series

• Potassium (Please) • Sodium (Send) • Lithium (Little) • Calcium (Charlie’s) • Magnesium (Monkeys) • Aluminium (And) • Carbon (Cute) • Zinc (Zebras) • Iron (In) • Hydrogen (Hot) • Copper (Cages) • Silver (Securely) • Gold (Guarded)

Only metals above hydrogen in the reactivity series will react with dilute acids.

metal + acid ⟶ salt + hydrogen

• Mg (s) + H2SO4 (aq) → MgSO4 (aq) + H2 (g) • Mg (s) + 2HCl (aq) → MgCl2 (aq) + H2 (g)

No it doesn’t, it is highly unreactive.

This means that a more reactive metal will displace a less reactive metal from its compounds.

Oxygen and water must be present for rust to occur.

• Barrier methods • Sacrificial protection • Galvanising

• Rust is prevented by coating iron with barriers (like paint, oil, grease, or electroplating) to block water and oxygen. • If coatings are damaged, iron is exposed and begins to rust. • Rust is porous, allowing air and water through, causing continuous internal corrosion even beneath broken barriers.

• A more reactive metal (like zinc) can be attached to iron. • The more reactive metal oxidises and corrodes first, protecting the iron. • Zinc loses electrons more easily than iron. • To keep protection, zinc bars must be replaced before they fully corrode.

• Galvanising coats iron with zinc (by electroplating or dipping in molten zinc). • Zinc reacts with air to form ZnCO₃, acting as a barrier. • If scratched, zinc still protects iron through sacrificial protection by corroding first.

If you have been reduced, you are the oxidising agent.

If you have been oxidised, you are the reducing agent.

Potassium

Sodium

Lithium and Calcium

Very slowly with water, but rapidly with steam

Zinc and Iron

Copper