This is an acid-base reaction (neutralization): Zn(OH)2 is an acid, KOH is a base.
Reactants:
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Zn(OH)2
Names: Zinc hydroxide, Zinc(II) hydroxide
Appearance: White powder
KOH – Potassium hydroxide
Other names: Caustic potash, Lye, Potash lye
Appearance: White solid, deliquescent ; White hygroscopic solid in various forms ; Odorless, white or slightly yellow lumps, rods, flakes, sticks, or pellets. [Note: May be used as an aqueous solution.]
Products:
K2ZnO2
H2O – Water, oxidane
Other names: Water (H2O), Hydrogen hydroxide (HH or HOH), Hydrogen oxide
Appearance: White crystalline solid, almost colorless liquid with a hint of blue, colorless gas
2 + 2 KOH → K2ZnO2 + 2 H2O – Balanced equation){kind=link}