Chemistry

What is the molecular mass of a substance X if 1.00 L of a solution containing 4, 5 g of X has an osmolality of 0.337 mmHg the 30° C?

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asked by Caline
  1. ∏ = MRT = [moles/Vol(Liters)]RT => moles = (∏·Vol(Liters)/RT) = mass(gms)/Mol Wt

    Solve for Mol Wt = [mass(gms)·R·T/∏·Vol(Liters)]

    Mass = 4.5-gms
    R = (0.08206 L-Atm/mole-K)
    T = (30 + 273)K = 303K
    ∏ = (0.337/760)Atm = 4.4 x 10^-4 Atm
    Vol(Liters) = 1.00 Liters

    Substitute into Mol Wt Equation above => 252,000 g/mol

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  2. Thanks :)

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    posted by Caline

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