A 7.3x10^-2 mg sample of protein is dissolved in H2O to make 0.25ml of solution. The osmotic pressure of solution is 0.56 torr at 25 degrees Celsius. what is the molar mass of the protein.
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Pi = i M R T
where
i is the dimensionless van 't Hoff factor
M is the molarity
R = 62.363 L Torr K−1 mol−1
is the gas constant
T is the thermodynamic (absolute) temperature
here M = .56 / 1 x 62.363 x (25+273) =3.013 x 10 ^-05 moles / liter
we also have 7.3x10^-5 g in .25 mL or 7.3x10^-5 x 1000 / .25 g in 1 liter = 0.292 g per liter
we in 1 liter have 0.292 g of solute = 3.013 x 10 ^-05 moles
mass of 1 mole = 0.292 g / 3.013 x 10 ^-05 mol = 9700 g / mole .. molar mass of the protein
where
i is the dimensionless van 't Hoff factor
M is the molarity
R = 62.363 L Torr K−1 mol−1
is the gas constant
T is the thermodynamic (absolute) temperature
here M = .56 / 1 x 62.363 x (25+273) =3.013 x 10 ^-05 moles / liter
we also have 7.3x10^-5 g in .25 mL or 7.3x10^-5 x 1000 / .25 g in 1 liter = 0.292 g per liter
we in 1 liter have 0.292 g of solute = 3.013 x 10 ^-05 moles
mass of 1 mole = 0.292 g / 3.013 x 10 ^-05 mol = 9700 g / mole .. molar mass of the protein