Raoults law practice test PDF

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Chem 4, Dr. La Gattuta

E/C HW Raoult’s Law & Henry’s Law

p.1

Name ________________________________________________ IMPORTANT: E/C HW’S must include FORMULAS/PLUG-IN’S & SOLVES AND MUST BE NEATLY DONE OR THEY WILL BE RETURNED WITH NO CREDIT GIVEN

1) A solution is prepared by dissolving 396 g of sucrose (342.2948 g/mol) in 624.0 g of water (18.01528 g/mol) at 30.0 °C. What is the vapor pressure of this solution? (The vapor pressure of water is 31.82 mmHg at 30.0 °C.)

b) Calculate the Vapor Pressure lowering.

2. The Partial Pressure of O2 gas in a person’s lungs varies from 22.0 mm Hg to 40.0 mm Hg. Calculate the Molarity of O2 that can dissolve in water at 25.0oC if the Partial P of O2 is 350 mm Hg and Henry’s Law Constant is 1.66 x 10-6 M/mm Hg at 25.0oC?

Chem 4, Dr. La Gattuta

E/C HW Raoult’s Law & Henry’s Law

p.2

Name _______________________________________________________ 3. What is the concentration of O2 in g/L water in a freshwater steam in equilibrium with the air at 25.0oC if the atmospheric pressure is 1.10 atm, Henry’s Law Constant is 1.66 x 10-6 M/mm Hg at 25.0oC? Assume the air is 21% Oxygen.

4) The vapor pressure of carbon tetrachloride, CCl4 (153.811 g/mol) at 50.0 °C is 0.437 atm. When 7.42 g of an electrolyte with a van’t Hoff factor of 3 is dissolved in 100.0 g of carbon tetrachloride, the vapor pressure of the solution is 0.411 atm. Calculate the molar mass of the electrolyte.

Chem 4, Dr. La Gattuta

E/C HW Raoult’s Law & Henry’s Law

p.3

Name ______________________________________________________ 5) Solubility can be expressed as moles per liter (Molarity) or grams per liter or grams per milliliter. If a gas in solution has a solubility of 0.086 g/L at a pressure of 3.5 atm, what pressure is required to attain a solubility of 2.3 g/L?

6) The solubility of a gas in water is 0.22 g/L at 20.0 kPa of pressure. What is the solubility in grams/mL when the pressure is increased to 115 kPa?

7. How many grams of carbon dioxide gas (44.0095 g/mol) are dissolved in a 2.00 L bottle of carbonated water if the manufacturer uses a pressure of 2.40 atm in the bottling process at 25.0 °C? Given: KH of CO2 in water = 3.4 x 10-2 mol/L atm at 25.0°C

Chem 4, Dr. La Gattuta

E/C HW Raoult’s Law & Henry’s Law

p.4

Name _______________________________________________________ 8a) What is the vapor pressure of water above a solution in which 32.50 g of Sodium Chloride, NaCl (58.44 g/mol) are dissolved in 125.0 g of water (18.01528 g/mol) at 343 K? The vapor pressure of pure water at 343 K is 233.7 torr.

b) How much was the Vapor P of water lowered with the addition of the Sodium Chloride?

9. If 27.0 grams of Acetylene, C2H2 (26.0373g/mol) dissolve in 375.0 mLs of water at 1.25 atm pressure at 25.0 oC. a) Calculate Henry’s Law Constant.

b) What is the solubility of Acetylene if the Partial P of C2H2 is 0.750 atm...