---
title: "Precipitate — AP Chem Definition, Ksp & Exam Guide"
description: "A precipitate is the insoluble solid that forms when two aqueous solutions react. It powers gravimetric analysis FRQs, Unit 4 reaction types, and Unit 7 Ksp."
canonical: "https://fiveable.me/ap-chem/key-terms/precipitate"
type: "key-term"
subject: "AP Chemistry"
---

# Precipitate — AP Chem Definition, Ksp & Exam Guide

## Definition

A precipitate is a solid substance that forms when two aqueous solutions react and produce an insoluble compound. It appears as fine particles suspended in the solution or as a solid settling at the bottom.

## Review

### Related Terms

- [Aqueous Solution](/ap-chem/key-terms/aqueous-solution): A solution where water is the solvent, meaning it is what dissolves other substances.
- [Solubility Rules](/ap-chem/key-terms/solubility-rules): Guidelines used to predict whether an ionic compound will be soluble or insoluble in water based on the combination of its ions.
- Supernatant: The clear liquid above a precipitate after it settles at the bottom of a container.