---
title: "Phase Change — AP Physics 2 Definition & Exam Guide"
description: "Phase change is the transition between solid, liquid, and gas, where energy flows as latent heat while temperature holds constant. Know both meanings on the AP exam."
canonical: "https://fiveable.me/ap-physics-2-revised/key-terms/phase-change"
type: "key-term"
subject: "AP Physics 2"
---

# Phase Change — AP Physics 2 Definition & Exam Guide

## Definition

Phase change refers to the transition between different states (phases) of matter, such as solid, liquid, gas, or plasma. During phase changes, energy is either absorbed or released while temperature remains constant.

## Related Study Guides

- [6.6 Interference and Diffraction](/ap-physics-2-revised/unit-6/interference-diffraction/study-guide/jpgWXdzP7Lo8aqyhlmVZ)

## Review

### Related Terms

- Latent Heat: The amount of heat energy required or released during a phase change without changing the temperature of the substance.
- Melting Point: The specific temperature at which a substance changes from solid to liquid phase.
- Boiling Point: The specific temperature at which a substance changes from liquid to gas phase.