The vapor pressure of water at 45.0 °C is 71.93 mmHg.Calculate the vapor pressure of a solution of 1.50m K₂CO₃ at this temperature (assume 100% dissociation) A)1.89 mmHg B)5.39 mmHg C)66.5 mmHg D)70.0 mmHg E)108 mmHg

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Quizplus · Accepted Answer

The vapor pressure of the solution is calculated using Raoult's Law. K2CO3 dissociates into 3 ions (2K+ and CO3^2-), so the van't Hoff factor (i) is 3. The molality is 1.50m, so the effective molality is 4.50m. The mole fraction of water is calculated as 1/(1+4.50) = 0.1818. The vapor pressure of the solution is 71.93 mmHg * 0.8182 = 66.5 mmHg.

The Vapor Pressure of Water at 45