When calcium hydroxide (Ca(OH)₂) reacts with hydrogen phosphate (H₃PO₄), the following reaction occurs:

3Ca(OH)₂ + 2H₃PO₄ → Ca₃(PO₄)₂ + 6H₂O

This reaction produces calcium phosphate (Ca₃(PO₄)₂) and water (H₂O).

Let me break down the reaction:

* Calcium hydroxide (Ca(OH)₂) is a base.

* Hydrogen phosphate (H₃PO₄) is an acid.

* Calcium phosphate (Ca₃(PO₄)₂) is an ionic compound.

* Water (H₂O) is a neutral molecule.

This is a neutralization reaction where the base and acid react to form a salt (calcium phosphate) and water.