In the extraction of silver, zinc metal is used as a reducing agent. The overall reaction can be written as: 2Ag(CN)‌2− + Zn → [Zn(CN)‌42−] + 2Ag Here, zinc replaces silver from the silver cyanide complex, reducing it to silver metal. The zinc ion formed in the reaction forms a complex with four cyanide ions. The structure of [Zn(CN)‌42−] can be represented as a tetrahedral complex with the zinc ion at the center and the four cyanide ions at the corners. The cyanide ions act as ligands and coordinate to the central zinc ion through their lone pairs of electrons, forming coordinate covalent bonds.