What mass of ethylene glycol,when mixed with 225 g H₂O,will reduce the equilibrium vapor pressure of H₂O from 1.00 atm to 0.800 atm at 100 °C? The molar masses of water and ethylene glycol are 18.02 g/mol and 62.07 g/mol,respectively.Assume ideal behavior for the solution. A) 15.6 g B) 49.9 g C) 194 g D) 969 g E) 3.10 × 10³ g

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The vapor pressure lowering is due to the presence of a non-volatile solute (ethylene glycol). Using Raoult's Law, the mole fraction of water is 0.8. Calculate moles of water (225 g / 18.02 g/mol) and solve for moles of ethylene glycol needed to achieve this mole fraction. Convert moles of ethylene glycol to grams using its molar mass.

What Mass of Ethylene Glycol,when Mixed with 225 G H2O,will

What Mass of Ethylene Glycol,when Mixed with 225 G H₂O,will