Chemistry 122 (Tyvoll)
EXAMINATION II
March 28, 2008
Part I. Multiple Choice (3 points each -- Total points = 45)
1. If two liquids are miscible, they _____ because _____.
1. mix together; their intermolecular interactions are similar
2. The process of forming a solution occurs in three parts: separating solvent molecules,
separating solute particles, and forming new solute-solvent associations. These three
processes are, respectively,
2. endothermic, endothermic, and exothermic.
3. Consider the equilibrium reaction where 2N2(g) + O2(g) ' 2N2O(g)
In a particular experiment, the equilibrium concentration of N2 is 0.048 M, O2 is 0.093 M,
and N2O is 6.55 × 10−21 M. What is the value of the equilibrium constant, KC?
−37
2. 2.0 × 10
4. The pressure inside a soda bottle is two atmospheres (1520 mmHg). If exactly half this
pressure is generated by CO2, what is the solubility of carbon dioxide in a 2 L bottle of root
beer at 40 oC? The Henry's Law constant for CO2 is 4.45 × 10-5 M/mmHg.
4. 0.0338 M
5. A solution with solute concentration equal to the solubility is said to be
will dissolve in such a solution.
; _____ solute
4. saturated; no more
6. What is the mole fraction of glucose in a solution of prepared by dissolving 23.8 g of
glucose (180.16 g/mol) in 250 g of water (18.015 g/mol)?
4. 0.00942
7. Increasing the temperature of water containing a dissolved gas will almost always
1. decrease the solubility of the gas
8. A particular chemical reaction is
3. either product-favored or reactant-favored depending on the temperature of the reaction
1
9. Molality (m) is defined as moles of solute per _____ of
.
2. kg; solvent
10. In living systems, a solution with a higher solute concentration than the surrounding cells is
said to be
. This causes water to flow _____ the cells by osmosis.
2. hypertonic; out of
11. Which one of the following aqueous solutions would be expected to freeze at the lowest
temperature?
4. 0.24 m NaCl
12. Given that the value of Kf for water is 1.86°C/m, what is the freezing point of an aqueous
solution of NaCl prepared by mixing 3.65 mol NaCl with 0.500 kg of water?
3. −13.6 oC
13. Which one of the following is not a conjugate acid-base pair?
3. H2SO3 and HSO4−
14. If the reaction quotient, QC, is greater than the equilibrium constant, KC, then
5. the reaction will proceed in the reverse direction
15. What is the chloride ion (Cl1−) concentration in a solution containing 0.525 mol MgCl2
dissolved in 1500 mL of solution?
2. 0.700 M
2