Chemistry / Unit 2 Chem 0300 short lesson, about 20 seconds
Variable-Charge Metals
Captions available
The idea
Many transition metals and some main-group metals form more than one stable cation charge, unpredictable from their periodic-table position alone.
In practice
Iron forms both Fe2+ and Fe3+, and copper forms both Cu+ and Cu2+, each pair stable in different compounds.
Where people slip
A single formula like "iron chloride" is genuinely ambiguous here — FeCl2 and FeCl3 are different compounds needing different names.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Something wrong in this lesson? Flag it · Sources for Chemistry