Activity Series
Definition and meaning of Activity Series in chemistry.
The activity series is an ordered list of elements (typically metals) ranked by their ability to lose electrons and form positive ions, used to predict which metal will displace another in a chemical reaction.
In more detail
The series is based on each element's standard reduction potential, a quantitative measure of the tendency to be reduced (gain electrons). Metals with lower (more negative) reduction potentials have a greater tendency to lose electrons and rank higher in the activity series. Metals positioned higher in the series are more reactive and will spontaneously displace lower metals from their compounds. This ranking is fundamental to predicting single displacement reactions and understanding redox chemistry across the periodic table.
Key facts
| Field | Inorganic Chemistry |
|---|---|
| Based on | Standard reduction potential (measured in volts) |
| Order (most to least reactive) | Lithium → Potassium → Sodium → Magnesium → Aluminum → Zinc → Iron → Copper → Gold |
| Primary use | Predicting single displacement and redox reactions |
When iron metal is added to copper sulfate (CuSO4) solution, iron displaces copper metal, producing iron sulfate (FeSO4) and copper metal. This occurs because iron ranks higher in the activity series than copper and more readily loses electrons.
Frequently asked questions
Why does a metal higher in the activity series displace a lower one?
Higher metals have a greater tendency to lose electrons (lower reduction potential). The reaction is thermodynamically favorable because the more reactive metal donates electrons to ions of the less reactive metal.
Can nonmetals be included in an activity series?
Yes, though the series is most commonly applied to metals. A nonmetal activity series ranks nonmetals by their electron-gaining ability using reduction potentials.