Chemical reactions are always accompanied by a temperature change.

Is it true that chemical reactions are always accompanied by a temperature change?

Partly. Sources split: some reference works say chemical reactions are accompanied by heat absorption or release and temperature change, while others note reactions can be isothermal or show no temperature change, so the universal 'always' is only partially addressed on both sides.

Verdict: CONTESTED PARTIAL · 3 sources for, 4 against · Last checked 17 Oct 2026

The private library was unavailable for some searches in this check. Missing library results are not evidence against the claim.

Handbook of Thermal Analysis and Calorimetry. (2018). play.google.com. https://play.google.com/store/books/details?id=AQMxDwAAQBAJ&source=gbs_api

Chemical reaction - Wikipedia. (n.d.). en.wikipedia.org. https://en.wikipedia.org/wiki/Chemical_reaction

the-new-encyclopedia-1914. (n.d.). archive.org. https://archive.org/details/the-new-encyclopedia-1914

collection-of-mathematics-dictionary-and-encyclopedia-books. (n.d.). archive.org. https://archive.org/details/collection-of-mathematics-dictionary-and-encyclopedia-books

5.1: Chemical Changes and Chemical Reactions. (n.d.). chem.libretexts.org. https://chem.libretexts.org/Bookshelves/Introductory_Chemistry/Book%3A_Introductory_Chemistry_Online_(Young)/05%3A_Chemical_Reactions/5.1%3A_Chemical_Changes_and_Chemical_Reactions

Characteristics of chemical reactions. (2020). chemistry.stackexchange.com. https://chemistry.stackexchange.com/questions/135659/characteristics-of-chemical-reactions

Energy Utilization through Coupled Systems. (1960). doi.org. https://doi.org/10.2307/3583614