Redox: follow the electrons
Oxidation corresponds to electron loss and reduction to electron gain in the electron-transfer view.
Start with the idea
Oxidation corresponds to electron loss and reduction to electron gain in the electron-transfer view.
A concrete example
In a redox reaction, oxidation and reduction always occur together: electrons lost somewhere are gained elsewhere.
Mendeleev’s tip
Do not start with a formula. Identify what changes, what stays constant and which quantity you are trying to explain or calculate.
Go one step deeper
In Zn + Cu²⁺ → Zn²⁺ + Cu, zinc loses two electrons while Cu²⁺ gains them. The two half-reactions balance electron by electron.
A trend or model is not an exceptionless law. Always check the quantity’s definition and the conditions being compared.
Check your understanding
Can you explain the phenomenon in your own words before looking at an equation?