Question

Determine the required concentration (in percent by mass) for an aqueous ethylene glycol solution to have...

Determine the required concentration (in percent by mass) for an aqueous ethylene glycol solution to have a boiling point of 104.0C . What is its freezing point?

DATA:

For pure water to 1 atm :

Cryoscopic constant (Kc)= 1,86 ªC/m

Ebulloscopic constant (Kb)= 0,52ªC/m

Boiling Point= 100ªC

Freezing point= 0ªC

For aqueous ethylene glycol solution

Boiling Point: 104ªC

WM(Ethylen glicol): 62,07g/mol (MSDS Data)

Calculation of %w of ethylene glycol

Calculation of weight of ethylene glicol dissolved in solution

Calculation of % mass

%

The requerid concentration for an aqueous ethylene glycol solution to have a boiling point of 104,0 is 47,8%.

Calculating the freezing point.

(C is ºC)

difference of temperature is 14,3ºC respect boiling point of pure water to 1 atm (0ºC), final freezing point is -14,3ºC,

The presence of ethylene glycol in the water, affects the colligative properties, such as boiling point and the freezing point.