Examples
Sodium forms Na⁺, potassium forms K⁺, magnesium forms Mg²⁺, calcium forms Ca²⁺, aluminum commonly forms Al³⁺, and iron can form Fe²⁺ or Fe³⁺.
Applications and misconceptions
Cations are central to batteries, salts, electrolysis, nerve signals, and minerals. A cation is not a positive electron; it is an atom or group with fewer electrons than protons.