Chemistry Quiz exam 4

What is the molar mass of 0.02 g of a protein dissolved in 25.0 mL of solution that has an osmotic pressure of 0.56 torr at 25 °C?

• 3 x 10^5 g/mol

• 8 x 10^7 g/mol

• 3 x 10^4 g/mol

• 7 x 10^2 g/mol

• None of the above

Under what conditions may we expect dissolution of an ionic compound to be complete?

• High temperature

• Low concentrations

• High pressure

• Small volumes

• None of the above

What is the van’t Hoff factor for the complete dissolution of 0.724 g of CaCl₂ in 175 g of water?

• 2.3

• 2.5

• 2.8

• 3.0

• None of the above

How do colloids compare to suspensions and solutions?

• The particle sizes are intermediate between suspensions and solutions

• The particle sizes are smaller than that in solutions

• The particle sizes are bigger than that in suspensions

• The particle sizes are the same as those in both suspensions and solutions

• None of the above

Which part of a carboxylate salt (soap) is responsible for cleaning oil?

• The polar end

• The non-polar chain

• Both the non-polar and polar ends

• The metal ion

• None of the above

What is the boiling point of a solution of 1.0 g of glycerin, C3H8(OH)3, in 47.8 g of water? Assume an ideal solution (Kb = 0.512 °C/m, BP = 100.0 °C).

• 100.23 °C

• 100.57 °C

• 99.88 °C

• 100.12 °C

• None of the above

Which of the following is correct regarding the addition of Ethylene Glycol to water?

• The boiling point is lowered

• The freezing point is lowered

• The surface tension is increased

• The freezing point is elevated

• None of the above

What is the osmotic pressure of a 0.30 M glucose solution at 37 °C?

• 7.6 atm

• 0.91 atm

• 770 atm

• 92 atm

• None of the above

What best describes the process when the cell concentration is greater on the outside?

• Isotonic

• Hypertonic

• Hypotonic

• Osmosis

• None of the above

4.00 g of a nonelectrolyte is dissolved in 55.0 g of benzene. The freezing point is 2.32 °C. Assuming ideal solution behavior, what is the molar mass of this compound (FP = 5.5 °C, Kf = 5.12 °C/m)?

• 0.63 g/mol

• 0.035 g/mol

• 3.2 g/mol

• 1.1 x 10² g/mol

• None of the above