How can glass be a liquid if it's so hard?
Category: Chemistry Published: December 18, 2012
By: Christopher S. Baird, author of The Top 50 Science Questions with Surprising Answers and Associate Professor of Physics at West Texas A&M University
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Public Domain Image, source: Christopher S. Baird.
Glass is not a liquid in the strictest sense of the word. But it is also not a standard solid. The chemistry of glass is complex and research is ongoing, but the current consensus is that glass is a phase of matter all its own, known as an "amorphous solid". Scientists refer to any amorphous solid as a "glass". Glass transitions are highly complex and cannot be treated in the same way as traditional phase transitions, according to the textbook "Glasses and the Glass Transition" by Ivan S. Gutzow.