The reactivity series of metals

The reactivity series of metals is a chart listing metals in order of decreasing reactivity. In general, the more reactive a metal is:

  • the more vigorously it reacts with other substances
  • the more easily it loses electrons to form positive ions (cations)

We can examine the reactivity of metals by observing their reactions with oxygen, water, steam and whether it displaces other metals in displacement reactions.

This table summarises the reactions of some metals in the reactivity series. Hydrogen is included for comparison.

MetalReaction with oxygen (when heated and at room temperature)Reaction with waterReaction with steamReactivity
Potassium (K)Reacts vigorous when heated. Lilac flame and white solid formed. Tarnishes when freshly cut at room temperature Reacts vigorously. Floats on the surface. Moves and fizzes. Burns with a lilac flame. Heat is released. Crackle as it disappears. Colourless solution remains.Reaction too dangerous to be attempted.Most reactive
Sodium (Na)Reacts vigorously when heated. Yellow/orange flame and white solid formed. Tarnishes when freshly cut at room temperature Reacts vigorously. Floats on the surface. Moves and fizzes. Melts to form a silvery ball. Heat is released. Crackle as it disappears. Colourless solution remains.Reaction too dangerous to be attempted.
Calcium (Ca)Reacts vigorously with strong heating. Brick red flame and white solid formed. Slowly forms a surface oxide at room temperature Reacts readily. Fizzes. Grey solid rises then sinks. Heat is released. Grey solid disappears. Solution appears milky.Reaction too dangerous to be attempted.
Magnesium (Mg)Reacts readily with strong heating. White light and white solid formed. Slowly forms a surface oxide at room temperature Very slow reaction. A few bubbles of gas produced.Reacts on strong heating. White light and white solid formed.
Aluminium (Al)Reacts readily with strong heating as a powder. White solid formed. Slowly forms a surface oxide at room temperature No reactionReacts as a powder on strong heating. White solid formed.
Zinc (Zn)Reacts steadily when heated forming a yellow solid which changes to white on cooling. Slowly forms a surface oxide at room temperature No reactionReacts as a powder on strong heating. Yellow solid forms which changes to white on cooling.
Iron (Fe)Reacts readily when heated as iron filings. Orange sparks and black solid formed. Slowly forms a surface oxide at room temperature No reactionReacts as a powder on very strong heating. Black solid formed.
Copper(Cu)Reacts on heating to form a black solid. Slowly forms a surface oxide at room temperatureNo reactionNo reactionLeast reactive

Prescribed Practical C3 - Investigate the reactivity of metals