Chapter 16 · Oxidation and Reduction
16.5The Activity Series: Predicting Spontaneous Redox Reactions
10 min · two checks
Predict
Will copper metal dissolve in hydrochloric acid?
The idea
- Use the activity series to predict single replacement.
- Predict which metals dissolve in acid.
The activity series lists metals from most reactive to least: Li, K, Ca, Na, Mg, Al, Zn, Fe, Sn, Pb, then H, then Cu, Ag, Au, roughly. A metal will displace the ion of a metal below it. Zinc metal plus copper(II) ion produces copper metal and zinc ion. Copper metal plus zinc ion does nothing. The higher metal is the stronger reducing agent.
Hydrogen sits in the list as a reference. Metals above hydrogen dissolve in acids such as HCl, producing H₂. Metals below it do not, which is why copper plumbing survives vinegar and zinc does not. Nitric acid is a special case: its nitrate can oxidize metals that H⁺ cannot, so “does not dissolve in acid” means non-oxidizing acids. Gold sits at the bottom and needs extreme mixtures.
Keep these
- A metal displaces ions of metals below it.
- Metals above H dissolve in non-oxidizing acids and produce H₂.
- Copper and silver do not dissolve in HCl.