Wednesday, February 6, 2008

New and Improved About.com Chemistry Page


Today I'm making up a worksheet of experiments to do later in the week about solutions and precipitates, based on our "spine," The Joy of Chemistry. While I find the book helpful in organizing my lessons (and, of course, providing all my information), it hasn't worked for us as a read-aloud. So what I do is go through the chapter I want to cover, find the demonstrations that I think we can do (based on availability of materials and risk level) and type them up. Surprisingly, despite the analogy the authors make to "The Joy of Cooking," the "recipes" in their book are integrated right into the text. So unless you're reading it surrounded by your fully-appointed and ready-to-use laboratory, it's a little hard to do the demonstrations just using the book. To make them usable for us, I've been putting them into recipe form -- Explanation, List of Equipment and Ingredients, Directions. I told both co-author Monty Fetterolf and his publisher's PR person that if they don't come out with a new edition, I'm going to write my own companion volume when I'm done!

One other thing I've been doing is finding similar, related experiments to add to, modify or replace some of the demonstrations in the book that I feel could use improvement (or just can't resist tinkering with). My main source for this information has been Anne Helmenstine's Chemistry section at About.com. I just scooted over there to see what she had on our upcoming projects and saw the site has gotten a makeover. It's cleaner looking, and the ads have been toned way down, making it easier to find what you want. The current lead story is about making a "Do It Yourself Chemistry Lab." One interesting question discussed: "Is It Safe to Use Kitchen Glassware for Chemistry?" Helmestine writes:
I remember a chemistry experiment in analytical chemistry class where we were asked to take a piece of glassware from the storeroom, get it as clean as we could, and then the instructor rinsed it with acid and water and showed us the spectrum of the stuff that was still on the glass. As you would imagine, there were heavy metals and some dangerous organics. He was trying to illustrate that even 'clean' glassware isn't inert and can mess up an analysis, but it also went a long way to explaining why we shouldn't make coffee in the lab. Using dishes for chemistry projects isn't the same thing, but it may not be safe.
Her conclusion? Yes and no. "If I make slime or a smoke bomb I'll use dishes, but I'll be careful to rinse them immediately so that no one accidentally eats borax or saltpeter ... but there are exceptions. For example, I wouldn't make green fire in cookware. "

I know a certain 12-year-old that will appreciate my saving those particular links.

Update: Anne Helmenstine left a nice little comment to this post. And I couldn't asking why the little white dish in the green fire photo above looked so much like a Corningware ramekin. Her reply:
Um... (confession time)... that's because it is a Corning ramekin. I think what I said was I wouldn't use ceramic cookware, not that I didn't, lol. When I tried that project, I did not expect the methanol in the Heet to burn quite that hot. I'm surprised the ramekin didn't shatter. For future tests, I used a stainless steel mixing bowl.
Just so you know.

3 comments:

Azareal said...

Thank you very much for your kind words. I'm glad you like the changes to About Chemistry. If you have specific types of projects you would like to see added, I welcome requests.

Lorna said...

This is a fabulous blog. We are hoping to start our Ellen McHenry 'The Elements' course in a few weeks and I really appreciate the inspiration from your blog. Thank you!

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