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Q & A: sugar water

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Most recent answer: 10/22/2007
Q:
I am helping my thrid grader with a science project for school, but we are having trouble finding related topics about his chosen project. he is trying to find research on dissolving sugar in regular tap water and in distilled water, and which one does the sugar disolve faster in. If you know of any sites, or can help give us some things to learn on that I’d appreciate it. Thanks.
- Jen
san angelo, tx
A:
We've gotten several questions on sugar water revcently, so perhaps this answer can take care of most of them.

Sugar water is simply water in which some sugar has dissolved. The best way to tell whether sugar dissolves faster in distilled water or whatever type of tapwater is available in your town is to try the experiment yourself. The most important thing is to make sure that both types of water are at the same temperature. Of course you should also make sure to use the same amount of sugar and of water for each type of water, and to stir in the same way in the same container.

It really shouldn't be necessary to have a prediction before starting the experiment. Still, if you want to know my guess, it will hardly make any difference which type of water you use. Tap water often has some calcium salts and other trace contaminants, but it is not all that different from distilled water. If you are using very small amounts of sugar, the initial pH of the water may matter, and that can depend on the source.

Evidently this is a very popular assignment. I have no idea why, since the results are unlikely to be dramatic, and the principles involved are obscure.

Science education in this country often has shortcomings.

Mike W.

(published on 10/22/2007)

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