Hooray, Science!
Sep. 10th, 2009 12:42 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
lwoodThey Might Be Giants has a new children's-oriented album out, called Here Comes Science. The folks at BoingBoing put together this cheery video on the elements.
Thing I Did Not Know: chalk has sulfur in it. I thought it was calcium carbonate, but no! It's calcium sulfate.
Enjoy!
-- Lorrie
Thing I Did Not Know: chalk has sulfur in it. I thought it was calcium carbonate, but no! It's calcium sulfate.
Enjoy!
-- Lorrie
![[identity profile]](https://www.dreamwidth.org/img/silk/identity/openid.png){kind=small}
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Date: 2009-09-10 08:53 pm (UTC)Actually, the stuff generically called 'chalk' refers to several different compounds. Blackboard chalk is indeed usually calcium sulphate these days, but the rock chalk found for instance in many of British hills is calcite (calcium carbonate) and used to be used for writing. The term 'chalk' is still used even though the actual material is different, the same way that people still refer to "lead pencils" when they haven't contained lead for years.
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Date: 2009-09-10 09:10 pm (UTC)no subject
Date: 2009-09-10 09:18 pm (UTC)no subject
Date: 2009-09-10 10:33 pm (UTC)We'll have to get the CD. Thanks for posting!