Explore BrainMass
Share

Explore BrainMass

    molecular formula and empirical formula of the hydrocarbon

    This content was COPIED from BrainMass.com - View the original, and get the already-completed solution here!

    Complete combustion of a 0.0100 mol sample of a hydrocarbon, CxHy, gives 1.792 L of CO2 at STP and 1.261 g of H2O (a) What is the molecular formula of the hydrocarbon? (b) What is the empirical formula of the hydrocarbon?

    © BrainMass Inc. brainmass.com October 9, 2019, 8:43 pm ad1c9bdddf
    https://brainmass.com/chemistry/stoichiometry/molecular-formula-empirical-formula-hydrocarbon-160802

    Solution Preview

    Complete combustion of a 0.0100 mol sample of a hydrocarbon, CxHy, gives 1.792 L of CO2 at STP and 1.261 g of H2O (a) What is the molecular formula of the hydrocarbon? (b) What is the empirical formula of the hydrocarbon?

    First find the moles of CO2 by the ideal gas law:
    STP = 100 kPa and 273.15 K
    V = 1.792 L
    By ideal gas law,
    PV = nRT
    (100 kPa)(1.792 L) = n (8.31 L·kPa·K-1·mol-1)(273.15 K)
    So
    n = 0.0789 ...

    Solution Summary

    It determines the molecular formula and empirical formula of certain hydrocarbon. The solution is detailed and received a '5/5' rating from the student who originally posted the question.

    $2.19