- #1
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ok, sorry. Couple of dumb questions..
We had a lab last night, and one part involved testing the pH of various substances (we used the little strips of litmus paper and measured the color against a chart). My group tested pure water and we obtained a pH measurement of 7. Another group tested sugar water and obtained a pH of 6. One of the questions was if the OH- concentation of pure water and sugar water differed by a magnitude of 10 times or greater, and while it did, I can't figure out why. Why would the pure water be more basic? What is it about sugar that would make water more acidic? Should I trust the test result from the other group?
We also did an experiment related to capillary action, where we placed plastic straws and glass tubes of different sizes in beakers half full of water or half full of alcohol. In all cases the water climbed in the tube or straw. The alcohol also climbed, but not quite as high. One of the lab questions was "for capillary action to occur is it necessary for 1) only the fluid or 2) both the fluid and the tube to be polar?" My thought is that only the fluid would need to be polar. I think the plastic material is polar, but the glass is not. But I am not sure about this. Is it strictly the evaporating molecules on top that pull the water column upwards?
Thanks!
We had a lab last night, and one part involved testing the pH of various substances (we used the little strips of litmus paper and measured the color against a chart). My group tested pure water and we obtained a pH measurement of 7. Another group tested sugar water and obtained a pH of 6. One of the questions was if the OH- concentation of pure water and sugar water differed by a magnitude of 10 times or greater, and while it did, I can't figure out why. Why would the pure water be more basic? What is it about sugar that would make water more acidic? Should I trust the test result from the other group?
We also did an experiment related to capillary action, where we placed plastic straws and glass tubes of different sizes in beakers half full of water or half full of alcohol. In all cases the water climbed in the tube or straw. The alcohol also climbed, but not quite as high. One of the lab questions was "for capillary action to occur is it necessary for 1) only the fluid or 2) both the fluid and the tube to be polar?" My thought is that only the fluid would need to be polar. I think the plastic material is polar, but the glass is not. But I am not sure about this. Is it strictly the evaporating molecules on top that pull the water column upwards?
Thanks!