The Effects of Crystal Solutes on the Supercooling of Deionized Water (2013)

Undergraduate: Sneha Gadi

Faculty Advisor: Stephen Shafroth
Department: Physics & Astronomy

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Contrary to popular belief, the supercooling of water does not require clean water to occur. In fact it can occur in a range of samples from muddy water to water with silver iodide. Furthermore, the time samples of water spend supercooled can be controlled using crystal solutes that resemble the crystal structure of ice. In this research four overall samples of water were tested: plain deionized water, salt water, water with silver iodide, and water with ice dripped in regularly. It was observed that supercooling time diminishes as the solute's crystal structure approaches that of ice. The principle that governs this finding and is explored qualitatively and quantitatively in this experiment is that when water contains solute with ice-like crystal structure, congregation of water molecules near these nucleation sites encourages more rapid freezing. As a result, supercooling can be shortened or even completely turned off with the addition of certain solutes. This important finding can allow for control over the supercooling of water, which is remarkable since water prefers supercooling to freezing at zero degrees Celsius.