posted by Paulie on .
A 50/50 blend of engine coolant and water (by volume) is usually used in an automobile\'s engine cooling system. If your car\'s cooling system holds 4.00 gallons, what is the boiling point of the solution? Make the following assumptions in your calculation; at normal filling conditions, the densities of engine coolant and water are 1.11 g/mL and 0.998 g/mL respectively. Assume that the engine coolant is pure ethylene glycol (HOCH2CH2OH), which is non-ionizing and non-volatile, and that the pressure remains constant at 1.00 atm. Also, you\'ll need to look up the boiling-point elevation constant for water.
Convert 2 gallons ethylene glycol to mL then use density to calculate the mass.
Convert 2 gallons H2O to mL and use density to calculate the mass.
mols ethylene glycol = grams/molar mass
molality of the soln then is moles ethylene glycol/kg H2O
delta T = 1*Kb*molality.
You can look up Kb but I think it is 0.52. You should confirm that. Solve for delta T and add to 100 C to find new boiling point.