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Quick help

  1. Mar 18, 2005 #1
    quick help!!!

    Hi I need help with two quick questions... thanks in advance....

    With the same type of agitation and at the same temperature, why would sugar disolve in water much faster then salt does?

    discuss the idea that the standard of living in a society might be measured in units kJ/Person available in that society
  2. jcsd
  3. Mar 18, 2005 #2


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    The second is not a quick question, and both look like homework. Check the rules for homework help.
  4. Mar 18, 2005 #3


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    That's a damn good question. If anybody knows the answer, please send me a PM.
    My only guess is that sugar molecules don't stack too well. Sticking sugar molecules together would be like throwing Christmas lights into a bundle. There would be holes everywhere, and those holes would be big enough for water molecules to get in and start breaking stuff apart. Salt would be the exact opposite; it's more like stacking panes of glass. Everything would be very close together, and water can only "attack" the salt crystals from the outer edges.

    That energy per person thing is very straight forward. You don't need help with that.
  5. Mar 19, 2005 #4
    they are questions in my textbook. I'm a homeschool student so I dont really have homework. I just need help understanding these as I couldn't find the answers in my text!!....can anyone help me out???
  6. Mar 19, 2005 #5
    Can anyone help me answer my questions...sugar or salt??
  7. Mar 20, 2005 #6


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    Well, I imagine that it is somewhat related to the differences in the overall process of solvation for each as well as the type of bonding interaction experienced during solvation. The interaction between sugar and water will probably be stronger than sugar-sugar, water will solvate sugar through intermolecular hydrogen bonding.

    With a salt, such as NaCl, the overall process is a bit longer, you've got to break up the ordered lattice energy and the solvation is more ordered than with a sugar.

    Overall, sugar is more miscible in water, than the salt;like dissolves like.
  8. Mar 20, 2005 #7


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    water-water, hydrogen bonding

    sugar-water, hydrogen bonding

    salt-water, dipole-ionic interactions
  9. Mar 20, 2005 #8
    hey thanks generalchemtutor!!! it makes much more sense now!!!
  10. Mar 20, 2005 #9
    any hints on my other question
  11. Mar 20, 2005 #10


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    KJ/person just means how much food, oil, and electricity are available. Obviously more is better.
  12. Mar 20, 2005 #11
    thats it....lol...that doesn't help at all.........anyone else.....thanks though
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