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    A hydrocarbon which consists of 82.8 percentage by mass of carbon has an approximate relative molecular mass of 55

    What is its empirical formula and molecular formula

    Here is my working for empirical

    100-82.8=17.82

    I divided by the mr and then divided by the smallest number I didn't get the right answer plz help

    Answer is C2H5 and C4h10
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    what answer did you get?
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    (Original post by yeah1106)
    A hydrocarbon which consists of 82.8 percentage by mass of carbon has an approximate relative molecular mass of 55

    What is its empirical formula and molecular formula

    Here is my working for empirical

    100-82.8=17.82

    I divided by the mr and then divided by the smallest number I didn't get the right answer plz help

    Answer is C2H5 and C4h10
    Posted from TSR Mobile

    A hydrocarbon consists of hydrogen and carbon only. If 82.8% of the mass is carbon then what is the percentage mass of hydrogen?
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    Total mass ~ 55
    Mr of hydrogen: 1
    Mr of carbon: 12

    Mass of carbon: 82.8% of 55: 45.54
    Mass of hydrogen: 17.2% of 55: 9.46

    Moles = mass/Mr
    Carbon: 45.54/12 = 3.795
    Hydrogen: 9.46(/1)

    Ratio of carbon to hydrogen=
    3.795 : 9.46
    *divide by 3.795*
    1 : 2.5
    *times by 2*
    2 : 5

    So empirical formula = C2H5

    Posted from TSR Mobile
 
 
 
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