Science Buddies: "Ask an Expert"

My son did a science fair experiment to show that smaller particles dissolve faster than larger particles in hot water (140 F). The added particles were table sugar, coarse sea salt, and Splenda. We expected that the Splenda would dissolve the fastest, but the table sugar did. The Splenda dissolved quickly but had an extra swirl of particulates for a few extra seconds. Can you explain why?

ddportil - Not sure I can give you an accurate answer, but Splenda (trade name for sucralose) is made from sucrose, which is a combination of the two sugars fructose and glucose. Sucralose substitutes three chloride atoms for three hydroxyl or OH groups on the sucrose molecule. These chloride atom substitutions enable sucralose to pass through your body essentially unchanged (no calories). It's possible that this molecular change alters it's dissolvability compared to salt and sugar. There may be other trace ingredients added to give Splenda other mechanical properties. These are just thoughts on my part, not really science, perhaps others can shed more light.

Rick Marz