Well, I'll be....!
I learned it is true, you can make washing soda from ordinary baking soda.
I did some checking, and here is a brief explanation of the science behind it. The weblog Penniless Parenting, which was quoted here:
http://lifehacker.com/5947595/diy-washing-soda says it best:
The difference between baking soda and washing soda is water and carbon dioxide. Seriously. Baking soda's chemical makeup is NaHCO3 (1 sodium, 1 hydrogen, one carbon, and 3 oxygen molecules). Washing soda's chemical makeup is Na2CO3 (2 sodium, 1 carbon, and 3 oxygen molecules). When baking soda is heated up to high temperatures, it breaks down to become washing soda, water steam, and carbon dioxide.
Thank you Sandra!!! Knowing this can be a saving grace when I can't get washing soda in my local stores. (Apparently lots of folks around here are using it in recipes for making homemade laundry detergent, because WS is frequently out of stock.) On the other hand, baking soda is everywhere, and bulk prices are cheap-cheap (yay!) in the swimming pool supplies department in the big box stores.
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