This is an acid-base reaction (neutralization): Pb(OH)2 is an acid, NaOH is a base.
Reactants:
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Pb(OH)2 – Lead(II) hydroxide
Other names: Lead hydroxide, Plumbous hydroxide, Basic lead carbonate
Appearance: Blue amorphous powder
NaOH
Names: Sodium hydroxide, Caustic soda, Lye
Appearance: White, waxy, opaque crystals ; White hygroscopic solid in various forms ; Colorless to white, odorless solid (flakes, beads, granular form).
Products:
Na2PbO2
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