Solutions Test Practice 1

What is the new freezing point of 200 mL of water (Kf = -1.86 C) if 195 g of sucrose (C12H22O11) are added to it?

• 4.3C

• 5.3C

• -5.3C

• -8.3C

When 0.258 g of a molecular compound, benzoic acid, was dissolved in 40.0 g of benzene, the freezing point of the solution was lowered to 5.23 °C. What is the molecular weight of the benzoic acid? K_f for benzene is 5.12 °C/m. Normal Freezing point of benzene is 5.5 °C

• .00211g/mol

• 122 g/mol

• .0005g/mol

• 34.6g/mol

0.100 mole of NaCl is dissolved into 100.0 grams of pure H₂O. What is the mole fraction of NaCl?

• .982

• .018

• .001

• .333

210.0 g of the nonvolatile solute sucrose (C₁₂H₂₂O₁₁) is added to 485.0 g of water at 25.0 °C. What will be the pressure of the water vapor over this solution? (The vapor pressure of pure water is 23.8 torr at 25.0 °C.)

• 23.1

• 23.5

• 23.7

• 23.3

The vapor pressure of water above a solution of water and a nonvolatile solute at 25.0 °C is 19.3 mm Hg. What is the mole fraction of the solute? (The vapor pressure of pure water is 23.8 torr at 25.0 °C.)

• .811

• .189

• .777

• 1.23

How many grams of carbon dioxide gas is dissolved in a 1 L bottle of carbonated water if the manufacturer uses a pressure of 2.4 atm in the bottling process at 25 °C? KH of CO2 in water = 29.76 atm/(mol/L) at 25 °C

• 3.52g

• .08g

• .257g

• 5.41g