The liquid used in automobile cooling systems is prepared by dissolving ethylene

Question

The liquid used in automobile cooling systems is prepared by dissolving ethylene glycol (HOCH CH20H) in water. Ethylene glycol has a molar mass of 6207 g/mol and a density of 1.115 g/mL at 50.0 1st attempt See Periodic Table QSee Hint Calculate the vapor pressure at 50 C of a coolant solution that is 59.0:41.0 ethylene glycol-to-water by volume. At 50.0°C, the density of water is 0.9880 g/mL, and its vapor pressure is 92 torr. The vapor pressure of ethylene glycol is less than 1 torr at 50.0°c torr

Explanation / Answer

Here, provided,

Ethylene glycol water ratio = 59:41

Density of water= 0.9880 g/ml at 50 oC

Density of ethylene glycol = 1.11 g/ml

Vapor pressure of water = 92 torr

Now, since, Density = Mass/Volume

Mass of water = 41 x 0.98 = 40.18 g

Mass of ethylene glycol = 59 x 1.11= 65.49 g

Number of moles of ethylene glycol = (65.49 x1)/ 62.07 = 1.055 moles

Number of moles of H2O = (40.18 x 1) / 18 = 2.232 moles

Total number of moles = 1.055 +2.232 = 3.287

Mole fraction of water = 2.232/3.287 = 0.679

Therefore,

Vapor pressure of the solution = 0.679 x 92 torr = 62.46 torr

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.