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Homework Help: Basic (Very) chemistry

  1. Feb 3, 2006 #1
    Is the following a mixture, element, compound, solution (homogeneous)

    a) air ---im guessing solution because there is many different molecules and its clear

    b) gasoline ---i cant decide whether gas is a solution or compound. The gasoline is made up of hydrogen and carbon.


    oh one more question....

    when converting

    126 mm^3 to _____cm^3 ....how do you do that. I havent delt with squares and cubes before when converting. Is there a trick to it?. Thanks
     
  2. jcsd
  3. Feb 3, 2006 #2
    Air and gasoline are mixtures, air is a mixture of oxygen, nitrogen and other gases in trace quantities, gasoline is a mixture of Octane and other hydrocarbons.

    as for the conversion, I think you'll get 0.126 as the answer. to do it yourself , you have the conversion factor 1cm=10mm, cube both sides and you'll get 1000 mm^3 = 1 cm^3 so 1 mm^3 = 10^(-3) cm^3, multiply both sides by 126 to get the answer.
     
  4. Feb 4, 2006 #3
    I disagree with gasoline and air being mixtures. Here are a couple short definitions;

    Mixture, a material that can be separated by physical means into two or more substances.

    Solution, a mixture that is uniform in its properties throughout given samples.

    If you have gas or air, they are all equally mixed and can't be seperated by phsyical means.

    But, I could be wrong because for some reason those always confused me. If I was answering it, that is what I would put.

    If you cheat that last one and type it into google, you get the same answer as aalmighty did. :wink:
     
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