Everything that appears on chemistnate.com​ is uncopyrighted.

• That means I’ve put them in the public domain, and released my copyright on all these works.
• There is no need to email me for permission — use my content however you want! Email it, share it, reprint it with or without credit. Change it around, put in a bunch of swear words and attribute them to me. It’s OK.
• Attribution is appreciated but not required.
• I’d prefer people buy my ebooks, but if they want to share with friends, they have every right to do so.

If you'd like more information about this arrangement, read ZenHabits' Uncopyright explanation.