# 9: Exact and Inexact Differentials

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##### Chapter Objectives
• Understand the concept of the total differential
• Understand the concept of exact and inexact differentials.
• Be able to test whether a differential is exact or not.
• Understand how to integrate differentials along different paths.
• Understand the role of exact and inexact differentials in thermodynamics.

Thumbnail: These are just three of the infinitely many paths between a state at point A at some time to point B at some other time. A discussion of exact and inexact differentials is strongly connected to understanding the differences between paths and states (CC BY-SA 3.0; Matt McIrvin via Wikipedia)

This page titled 9: Exact and Inexact Differentials is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Marcia Levitus via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.