Colligative Properties - Page 6
Questions
- Glycerin, #C_3H_8O_3#, is a nonvolatile liquid. What is the vapor pressure of a solution made by adding 164 g glycerin to 338 mL #H_2O# at 39.8°C?
- Why do 0.60 grams of acetic acid dissolve in 200 grams of benzene to form a solution that lowers the freezing point of benzene to 5.40°C?
- How can freezing point depression determine purity?
- What is the vapor pressure of the pure solvent if the vapor pressure of a solution of 10.0 g of sucrose, #C_6H_12O_6#, in 100.0 g of ethanol is 55.0 mmHg?
- If a solvent contains a few impurities, how does its boiling point compare to the pure solvent?
- How would you calculate the vapor pressure of a solution made by dissolving 88.2 g of urea (molar mass = 60.06 g/mol) in 303 mL of water at 35°C? Vapor pressure of water at 35 degrees is 42.18 mm Hg.
- What mass of cholesterol should be dissolved in #"295 g"# of benzene to lower the freezing point by #"0.450 K"#? (#M = "386.6 g/mol"# for cholesterol and #"78.11 g/mol"# for benzene.)
- Both #NaCl# and #CaCl_2# are used to melt ice on roads and sidewalks in winter. What advantages do these substances have over sucrose or urea in lowering the freezing point of water?
- What is the molality of benzene in a solution that contains #"6.502 g"# of benzene in #"162.7 g"# of chloroform/#"CHCl"_3# (#K_f# for #"CHCl"_3# is #4.68^@ "C"cdot"kg/mol"# and #T_f^"*"# of #"CHCl"_3# is #63.5^@ "C"#)?
- Why is salt sprinkled on icy roads and sidewalk?
- Which solution will exhibit the GREATEST freezing point depression for #1*mol*L^-1# aqueous solutions of: #"(i) propanol; (ii) potassium bromide; (iii) calcium bromide?"#
- Consider 1.60 g of naphthalene (C10H8) is dissolved in 20.0 g of benzene. The freezing point of benzene is 5.5oC, and the freezing point of the mixture is 2.8oC. What is the molal freezing point constant for benzene?
- What is the freezing point of a 0.05500 m aqueous solution of #NaNO_3#, if the molal freezing-point-depression constant of water is 1.86°C /m?
- For an arbitrary nonelectrolyte, calculate the freezing point when #"0.0192 mols"# of it is dissolved in #"5.00 g"# of water? #K_f = 1.86^@ "C/m"# for water.
- What is the mol fraction of ethylene glycol in the solution phase for an aqueous solution with a vapor pressure of #"760 torr"# if the pure vapor pressure was #"1077 torr"#?
- Methanol, #CH_3OH# is used as an antifreeze. How many grams of methanol would you need per 1000.0 g of water for an aqueous solution to stay liquid at -20.0° C?
- A solution is prepared by dissolving 40.0 g of sucrose, in 250 g of water at 25°C. What is the vapor pressure of the solution if the vapor pressure of water at 25°C is 23.76 mm Hg?
- What is the boiling point (in °C) of a 1.56 m aqueous solution of #CaCl_2#?
- What is the molar mass of a non-electrolyte compound if 4.28 grams is dissolved in 25.0 grams of chloroform solvent to form a solution which has a boiling point elevation of 2.30 degrees celsius?
- Can someone clarify freezing point depression and boiling point elevation for me?