Sacrificial metal

A sacrificial metal is a metal used as a sacrificial anode in cathodic protection that corrodes to prevent a primary metal from corrosion, galvanization or rusting. When two metals touch each other and water is present, electrolysis occurs. One well known example is the reaction between zinc (Zn) and iron (Fe). Zn atoms ionize as it is more electronegative and is oxidized and corrodes. Zn(s)→Zn2+(aq) +2e (oxidation)