Chemicals Video Sources

These are the sources for my video on the scientific definition of the term chemical, seen here.

The colloquial definition of the word chemical comes from wiktionary, which defines chemicals as "an artificial chemical compound". There is of course a negative conotation about the definition seen in the example they provide ("I color my hair with henna, not chemicals"). The non-colloquial, scientific definition of the word chemical comes from three text books:

“Biology: A Guide to the Natural World Fifth Edition”; David Krogh; 978-0-321-61655-5; p. 22
“Chemistry: The Central Science 11th Edition”; Theodore L. Brown; 978-0-13-600617-6; p. 5
“Essentials of Geology 4th edition”; Stephen Marshak; 978-0-393-91939-4; p. 7

They all agree that a chemical is “matter that has distinct properties and a constant composition that does not vary from sample to sample and cannot be separated by physical means.”

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