All rights reserved. But one industry was struck very hard by the switch: the crack cocaine trade. Since I wasn't in the lab, I wasn't wearing my trusty goggles. In most cases that does not matter much, as tempered soda-lime glass is still pretty good at withstanding thermal shocks. The unintended consequence of World Kitchen’s switch? From the Archives: Half Baked: How crack cocaine led to the war against baking soda. The trademarked laboratory glassware Pyrex is an example of this type of glass. So, do not expect special non-breakability virtues. The oil and test tube have the same indices of refraction; that is, the speed of light passing through either medium is identical. followed by World Kitchen LLC which is making glass products by the registered trade name of Pyrex. Borosilicate and soda lime glass have a similar elastic modulus: 9.1 x 106 psi for borosilicate glass and 10.2 x 106 psi for soda lime glass. It turns out that turning cocaine into crack requires bringing the solution of water and powdered cocaine to a very high temperature and then rapidly cooling it. Modern American made pyrex no longer uses borosilicate glass. (It may, however, be more resilient to drops.) 3. R.C. Test tubes in chemistry labs are still made of borosilicate glass to avoid this very problem. Did you know that Pyrex glassware used in chemistry labs is different than Pyrex glassware used in kitchens? You can buy a ten pack of such test tubes for $10.99 with free shipping via Amazon Prime. Even the restaurant and food services industries can use the newer version of Pyrex without much concern. Of course, there are few cases where one is going to expose a Pyrex measuring cup to such extreme temperatures, so, if you do have a soda-lime one in your kitchen (and you probably do), there is little reason to worry — your recipes are almost certainly safe. To say I was shocked would be an understatement. On the other hand, soda lime glass has a high coefficient of thermal expansion (9 x 10-6 K-1), which means that it will undergo sizeable expansion upon heating and contraction upon cooling. Copyright © 2020 Division of Chemical Education, Inc. of the American Chemical Society. Before you submit, you should first read the Contribution page and then follow the link to the Contribution Guidelines. Pyrex is widely used in the laboratory work like test tubes, dishes and beakers as well as kitchen accessories, cooking utensils and baking vessels etc. 1. This special glass is especially resistant to thermal shock, but is also stronger and more durable than regular glass. Unfortunately when Corning, Inc. sold off the PYREX® trademark it became pyrex® in America and the new company started using Soda-Lime Glass instead of Borosilicate Glass. Those performing the demonstrations shown in this video have been trained and adhere to best safety practices. To learn more about this topic, check out the following: 1. Pyrex was produced in 1915 by Corning In. Could you let me know where they are available thank you. “How do I identify older, safer Pyrex vs. the newer "exploding" Pyrex glass cookware?” The best way is to look at the bottom of the product. PYREX (uppercase) is borosilicate glass whereas Pyrex is tempered soda lime glass in North America. After the sale, Corning continued to sell borosilicate glass for laboratory use under the Pyrex … PYREX (uppercase) is borosilicate glass whereas Pyrex is tempered soda lime glass in North America. The borosilicate glass is relatively inexpensive compared to other types of glass and glass-ceramics used in making that mirror blanks. What’s going on? Try the same thing with a measuring cup of soda lime glass, and the measuring cup will likely break, because in this case = 100 K > 54 K. I wish someone would have told me all this a few years ago…. Imagine my surprise one day in the early 2000’s when I decided it would be safe to boil water in a Pyrex measuring cup directly on the stovetop...the measuring cup cracked, sending broken glass and hot water all over the stove and floor! Please note: comment moderation is enabled and may delay your comment. Europe still uses PYREX or borosilicate glass. I like pizza over turkey, anyway! Companies like Pyrex use it as a safe material to make heat-resistant glass jugs, glass bottles, and cookware. Mostly I was glad I didn't get cut, or any glass in my eye. The PYREX patent was apparently sold but the Pyrex name has become synonymous with heat resistant glass but they are distinctly different glass. Using the appropriate values for each glass type in Equation 1, we see that borosilicate glass can experience a 183 K difference in temperature without shattering.