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    For some reason, I can't do this question. I can usually do % by mass composition things fine, but this one wont work for me. I'm probably just being retarded, but help?

    Calculate the empirical formula of X which has the following composition by mass -

    K - 32%
    Cr - 21.3%
    F - 46.7%

    RMM

    K - 39
    Cr - 52
    F 19
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    i get CrK2F6
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    32/39 = 0.820512820512820512820512820512 82
    21.3/52 = 0.409615384615384615384615384615 38
    46.7/19 = 2.457894736842105263157894736842 1
    --------------
    1/ 0.409615384615384615384615384615 38 = 2.441314553990610328638497652584 5
    --------------
    2.441314553990610328638497652584 5 * 0.820512820512820512820512820512 82 = 2
    2.441314553990610328638497652584 5 * 0.409615384615384615384615384615 38 = 1
    2.441314553990610328638497652584 5 * 2.457894736842105263157894736842 1 = 6
    --------------
    K2CrF6
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    agreed
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    (Original post by aMb)
    32/39 = 0.820512820512820512820512820512 82
    21.3/52 = 0.409615384615384615384615384615 38
    46.7/19 = 2.457894736842105263157894736842 1
    --------------
    1/ 0.409615384615384615384615384615 38 = 2.441314553990610328638497652584 5
    --------------
    2.441314553990610328638497652584 5 * 0.820512820512820512820512820512 82 = 2
    2.441314553990610328638497652584 5 * 0.409615384615384615384615384615 38 = 1
    2.441314553990610328638497652584 5 * 2.457894736842105263157894736842 1 = 6
    --------------
    K2CrF6




    hw the hell did you guys do this?
    isnt the empirical formula done by ratios?
    umm..i think i got it......but i dnt remember using percentages, they gaves us teh mass of each and u had to dvide by molecular mass, hw do u use the percentage to get the ratios?
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    Use just use the percentages as masses. It works out the same
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    thanks man, i was dyin a bit there :cool:
 
 
 
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