MadSci Network: Chemistry |
That's a neat question, and first I'll give you a hint -- is the soup the only thing being heated? The reason that it sometimes collapses a bit first is because, depending on the thickness of the walls and the size and shape of the container, sometimes the tupperware itself expands faster than its contents. Not for long, admittedly; the expansion of the soup, especially if it starts boiling, becomes much, much greater than the plastic.
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