Question

1) What is the equilibrium partial pressure of water vapor above a mixture of 62.2 g H₂O and 35.2 g HOCH₂CH₂OH at 55 °C. The partial pressure of pure water at 55.0 °C is 118.0 mm Hg. Assume ideal behavior for the solution.

2

Which of the following statements is INCORRECT?

	a)The solubility of a gas in water decreases with increasing temperature.
	b)The dissolution of a gas in water is usually an exothermic process.
	c)The solubility of a gas in water is proportional to the partial pressure of the gas above the water.
	d)The solubility of a gas in water is inversely proportional to the molar mass of the gas.
	e)The relationship between the solubility of a gas and its partial pressure is known as Henry's law.

Answer 1

Moles of water = mass/molar mass of H2O = 62.2 /18.015 = 3.4527

Moles of ethlene glycol = 35.2 /62.07 = 0.567

mol fraction of water = moles of water / ( total moles of mixture) = ( 3.4527 /3.4527+0.567) = 0.859

Partial pressure of H2O = mol fraction of H2O x vapor pressure of Pure H2O = 0.859 x 118 = 101.36 mm Hg

2) Solubility of gas increases as Molarmass of gas increases since bigger gas molecules will have more interactions and hence molre solubility

Hence statement D is wrong