Chem II Ch 13 Study guide

What is the osmotic pressure of a 0.200 Molar aqueous solution of glucose at 298K ?

4.89 atm

6.50x10-7 grams of arsenic is said to be 14.2 ppb of a certain mass of cow's milk. What is the mass of this cow's milk?

45.8g

The vapor pressure of water at 90°C is 0.692 atm. What is the vapor pressure (in atm) of a solution made by dissolving 5.82 mole(s) of glucose(s) in 1000 g of water? Assume that Raoult's law applies.

0.6260 atm

You have 14.2 grams of glycerol( molar mass = 92.09g/mole) added to 14.2 grams of water (molar mass = 18.02g/mole). What is the mole fraction of water in this solution?

0.837

If 2.00kg of drinking water contains 3.00x10-3 grams of copper, how many ppm's by mass is there of copper present?

1.50 ppm

The environmental protection agency has set a tolerable limit for lead in drinking water at 15ppb. If you have one liter of drinking water (1000g), how much lead by mass is permitted therein?

1.5x10-5 grams

What is the boiling-point for a solution containing 0.251 mol of naphthalene (a nonvolatile, nonionizing compound) in 250. g of liquid benzene? (Kbp = 2.53°C/m for benzene). Benzene has a normal boiling point of 80.4 oC at 1 atm.

82.9 degrees C

The solubility of 1-pentanol in water is 2.7 g per 100 g of water at 25°C. What is the maximum amount of 1-pentanol that will dissolve in 2.1 g of water at 25°C? a. 0.057 g b. 1.3 g c. 2.7 g d. 5.7 g e. 0.013 g

a. 0.057 g

What is the definition of molality? a. moles of solute per kg of solvent b. grams of solute per kg of solution c. grams of solute per liter of solution d. moles of solute per liter of solvent e. moles of solute per liter of solution

a. moles of solute per kg of solvent

What partial pressure of oxygen gas is required in order for 0.00284 g (8.875 x 10-5 moles ) of the gas to dissolve in 15.9 mL of pure water? The Henry's law constant for oxygen gas is 1.3 × 10-3 M atm-1. a. 2.3 × 10-7 atm b. 4.3 atm c. 1.2 × 10-7 atm d. 2.3 × 10-1 atm e. 4.2 × 10-2 atm

b. 4.3 atm

If 27.9 g LiCl is dissolved in 175 g H2O, what is the weight percent of LiCl in the solution? a. 0.376% b. 6.78% c. 13.8% d. 15.9% e. 19.0%

c. 13.8%

Which action(s) will decrease the equilibrium concentration of an inert gas (such as N2) in water? 1. decreasing the temperature of the water 2. increasing the volume of water 3. decreasing the pressure of the gas above the liquid a. 1 only b. 2 only c. 3 only d. 1 and 3 e. 1, 2, and 3

c. 3 only

The Henry's law constant for N2 in water at 25 °C is 6.0 × 10-4 mol/kg⋅bar. What is the equilibrium concentration of N2 in water when the partial pressure of N2 is 586 mm Hg? (760 mm Hg = 1 atm = 0.9869 bar) a. 1.4 × 10-9 M b. 1.8 × 10-5 M c. 4.6 × 10-4 M d. 7.7 × 10-4 M e. 7.9 × 10-4 M

c. 4.6 × 10-4 M

Which of the following statements is/are CORRECT? 1. Solubility is defined as the concentration of solute in equilibrium with undissolved solute in a saturated solution. 2. If two liquids mix to an appreciable extent to form a solution, they are miscible. 3. If two liquids mix completely in any proportion to form a solution, the resulting solution is supersaturated. a. 1 only b. 2 only c. 3 only d. 1 and 2 e. 2 and 3

d. 1 and 2

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

e. The solubility of a gas in water is inversely proportional to the molar mass of the gas.