Ch13 Solutions and colloids Page 1
Homework : Chapter 13 Solutions and colloids
PROBLEM 13.2 If air contains 78% N2 by volume, what is the solubility of N2 in
water at 25C and 1 atm (k H for N2 in H2O at 25C = 7x10-4 mol/L.atm)?
PROBLEM 13.3 How many grams of glucose (C6H12O6) must be dissolved in 563 g of
ethanol (C2H5OH) to prepare a 2.40x10-2 m solution?
PROBLEM 13.4 An alcohol solution contains 35.0 g of 1-propanol (C3H7OH) and 150
g of ethanol (C2H5OH). Calculate the mass percent and the mole fraction of each
alcohol.
PROBLEM 13.5 A sample of commercial concentrated hydrochloric acid is 11.8 M
HCl and has a density of 1.190 g/mL. Calculate the mass %, molality, and mole
fraction of HCl.
PROBLEM 13.6 Calculate the vapor pressure lowering of a solution of 2.00 g of
aspirin (M = 180.15 g/mol) in 50.0 g of methanol (CH3OH) at 21.2C. Pure methanol
has a vapor pressure of 101 torr at this temperature.
PROBLEM 13.7 What is the minimum concentration (molality) of ethylene glycol
solution that will protect the car’s cooling system from freezing at 0.00F? (Assume
the solution is ideal.)
PROBLEM 13.8 A 0.30 M solution of sucrose that is at 37C has approximately the
same osmotic pressure as blood does. What is the osmotic pressure of blood?
PROBLEM 13.9 The 0.100 m MgCl2 solution has a density of 1.006 g/mL at 20.0°C.
What is the osmotic pressure of the solution?