This is an acid-base reaction (neutralization): HCl is an acid, Ca(OH)2 is a base.
Reactants:
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HCl – Chlorane, Hydrogen chloride
Other names: Hydrochloric acid, M, Uriatic acid
Appearance: Colorless, transparent liquid, fumes in air if concentrated ; Colorless gas ; Colourless compressed liquefied gas with pungent odour ; Colorless to slightly yellow gas with a pungent, irritating odor. [Note: Shipped as a liquefied compressed gas.]
Ca(OH)2 – Calcium hydroxide
Other names: {{ubl, Slaked lime, Calcium hydrate
Appearance: White powder ; Colourless crystals or white powder ; White, odorless powder. [Note: Readily absorbs CO2 from the air to form calcium carbonate.]
Products:
CaCl2 – Calcium chloride
Other names: Calcium(II) chloride, Calcium dichloride, E509
Appearance: White powder, hygroscopic ; Odourless hygroscopic colourless or white crystals
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 → CaCl2 + 2 H2O – Balanced equation){kind=link}