4CH1
The Reactivity Series
Inorganic Chemistry · 1 question type
Standard order
- Comparing reactions with water, acids, oxygen, and other metals lets chemists rank the metals from most reactive at the top to least reactive at the bottom
| Position | Metal | Reaction with cold water | Reaction with acid | Reaction with oxygen |
|---|---|---|---|---|
| Most reactive | Potassium, K | Violent | (Too dangerous) | Burns easily, lilac flame |
| ↑ | Sodium, Na | Vigorous | (Too dangerous) | Burns, yellow-orange flame |
| ↑ | Lithium, Li | Steady | (Too dangerous) | Burns, red flame |
| ↑ | Calcium, Ca | Brisk | Vigorous | Burns, brick-red flame |
| ↑ | Magnesium, Mg | Very slow; fast with steam | Brisk | Burns with intense white flame |
| ↑ | Aluminium, Al | None (protective oxide layer) | Slow | Forms an oxide film |
| ↑ | Carbon, C | — (non-metal reference) | — | Burns; reduces some metal oxides |
| ↑ | Zinc, Zn | Slow with steam | Moderate | Burns, blue-green flame |
| ↑ | Iron, Fe | Slow with steam | Slow | Rusts in moist air |
| ↑ | Hydrogen, H | — (non-metal reference) | — | Burns to form water |
| ↑ | Copper, Cu | None | None | Surface darkens on strong heating |
| ↑ | Silver, Ag | None | None | None at normal temperatures |
| Least reactive | Gold, Au | None | None | None |
- Carbon and hydrogen are not metals but are placed in the series as reference points
- Carbon's position matters for industry: any metal below carbon (Zn, Fe, Cu, etc.) can be extracted from its oxide by heating with carbon, while metals above carbon (Al, Mg and higher) cannot — they must be extracted by electrolysis
- Hydrogen's position matters for acids: only metals above hydrogen react with dilute acid to release hydrogen gas
Exam tip
Stating why one metal displaces another
What comes up: a one-mark question asks you to explain why, for example, aluminium displaces iron in the thermite reaction, or why a predicted displacement reaction will (or will not) occur.
Write: state that the displacing metal is more reactive than the metal in the compound (or equivalently, that it is higher in the reactivity series). The mark scheme also accepts describing it as a better or stronger reducing agent.
Watch out: simply saying "it reacts" or "it is more vigorous" without a comparison to the other metal scores no mark — you must make the comparative claim explicit.