Intermolecular Forces
The forces of attraction between molecules of Cl₂ are?
London forces
What is the name given to the process when solvent molecules surround solute molecules?
(Answer: c) Solvation)
Which phase changes are exothermic?
(Answer: c) 3 only - Condensation)
Use a vapor pressure graph to determine the normal boiling point of O₂.
(Answer: b) 90 K)
The freezing point of a solution with 0.31 mol sucrose in 175 g of water is?
(Answer: d) -5.4°C)
The forces of attraction between molecules of I₂ are?
(Answer: d) London forces)
What is the mole fraction of water in a water-ethanol solution that is 54% water by mass?
(Answer: c) 0.46)
The mass of water that must evaporate to dissipate 1.7 × 10⁵ J of heat from the body is?
(Answer: c) 75.2 g)
The vapor pressure of diethyl ether is 401 mmHg at 18°C. What is its vapor pressure at 32°C?
(Answer: c) 530 mm Hg)
The mole fraction of ethanol in a solution with 46 g ethanol and 64 g methanol is?
(Answer: b) 0.42)
Among N₂, H₂, and CO, which has the highest boiling point?
(Answer: b) CO)
The number of grams of oxalic acid dihydrate needed to prepare 250.0 mL of 1.25 M solution is?
(Answer: c) 43.6 g)
The amount of heat released to convert 20.0 g of mercury vapor at 387°C to liquid at 307°C is?
(Answer: b) 6.56 kJ)
A 500.0 mL sample of water contains 692 μg of lead. What is the concentration in ppm?
(Answer: b) 4.0 ppm)
The percent Na₂CO₃ by mass in a 1.50 molal aqueous solution is?
(Answer: c) 11.6%)
Among HF, HBr, HCl, and HI, which has the highest boiling point?
(Answer: a) HF)
A concentrated H₂SO₄ solution is 65% by mass and has a density of 1.55 g/mL. What is its molality?
(Answer: d) 18.9 m)
The triple point of I₂ occurs at 0.12 atm and 115°C. What does this mean?
(Answer: a) Liquid I₂ cannot exist under these conditions)
The vapor pressure of a solution with 115 g of urea in 485 g of water at 25°C is?
(Answer: b) 23.3 mm Hg)
The vapor pressure of a solution containing a nonvolatile solute is directly proportional to?
(Answer: d) Mole fraction of solvent)
Among covalent solids, molecular solids, metallic solids, and ionic solids, which generally shows electrical conductivity?
(Answer: d) Metallic solid)
A 1.0 g protein sample (MW = 50,000 g/mol) is dissolved in 50.0 mL of water. What is its osmotic pressure at 25°C?
(Answer: c) 7.4 mmHg)
In a certain mountain range, water boils at 95.0 oC. What is the atmospheric pressure under these conditions, in mm Hg? The heat of vaporization, ∆H vap for H2O is 44.0 kJ/mole, and the normal boiling point of H2O is 100.0 oC.
(Answer: b) 628 mm Hg)
Sparkling wine is bottled under 4.0 atm of CO₂ pressure, where CO₂ solubility is 0.68 g/100 g H₂O. After opening, at 4.0 × 10⁻⁴ atm, what is the new solubility?
(Answer: c) 5.1 × 10⁻⁶ g/100 g H₂O)
Which choices increase gas solubility in a liquid?
(Answer: e) Both a and b - Increasing pressure & decreasing temperature)