Chemistry is a "branch of science concerned with the study of the structure and composition of the different kinds of matter, the changes that matter may undergo, and the phenomena which occur in the course of these changes."
Helicon (Ed.). (2018). Chemistry. In The Hutchinson Unabridged Encyclopedia with Atlas and Weather Guide. Helicon. https://search.credoreference.com/articles/Qm9va0FydGljbGU6NTA1MTIx?aid=20878