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gas volume question Watch

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    can someone explain the theory behind this question? i would have thought the answer is ethane?Name:  chem.PNG
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    you would use the formulas

    n=m/Mr then n=v/24
    if you wanted to do it the long way
    but you can tell from the relative mass that ethane would have the greatest
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    (Original post by happiness12)
    you would use the formulas

    n=m/Mr then n=v/24
    if you wanted to do it the long way
    but you can tell from the relative mass that ethane would have the greatest
    the answer's D though...
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    (Original post by gomc)
    can someone explain the theory behind this question? i would have thought the answer is ethane?Name:  chem.PNG
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    1 mole of any gas will fill the same volume at a given temperature and pressure according to the ideal gas law (pV=nRT).

    This means that when we think about taking 1 gram of a substance, the gas with the largest volume will be the one with the smallest atomic/molecular mass. This is because 1 gram of a light gas consists of more atoms/molecules than 1 gram of a heavy gas.

    If we think about these gases (using the atomic masses given) ethane (C2H6) has a mass of 30 amu;
    Oxygen exists as O2 mass 32 amu; Fluorine exists as F2 mass 38 amu; Ne exists as atoms mass 20 amu
    so 1 gram of neon must have the largest volume.
 
 
 
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