Multiple Choice
Identify the
choice that best completes the statement or answers the question.
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1.
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A heterogeneous mixture always contains
a. | only one substance. | b. | more than two substances. | c. | two or more
substances that are visibly distinguishable. | d. | two or more substances that are not visibly
distinguishable. |
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2.
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All of the following are homogeneous mixtures EXCEPT
a. | sodium chloride. | c. | gasoline. | b. | a sugar-water solution. | d. | a salt-water
solution. |
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3.
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All of the following are heterogeneous mixtures EXCEPT
a. | whole-wheat bread. | c. | tap water. | b. | granite. | d. | an oil-water
mixture. |
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4.
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Water in air is an example of which solute-solvent combination?
a. | gas-liquid | c. | liquid-liquid | b. | liquid-gas | d. | gas-gas |
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5.
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Sugar in water is an example of which solute-solvent combination?
a. | gas-liquid | c. | solid-liquid | b. | liquid-liquid | d. | liquid-solid |
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6.
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Which mixture contains visible particles that settle out unless the mixture is
stirred?
a. | a colloid | c. | a solution | b. | a homogeneous mixture | d. | a suspension |
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7.
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Colloids
a. | can be separated by filtering. | c. | scatter light. | b. | settle out when
allowed to stand. | d. | are
heterogeneous. |
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8.
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A substance whose water solution conducts a current is a(n)
a. | nonelectrolyte. | c. | nonpolar substance. | b. | electrolyte. | d. | solute. |
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9.
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Which of the following is a molecular substance whose water solution conducts
electricity?
a. | liquid hydrogen | c. | sugar | b. | hydrogen chloride | d. | iron |
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10.
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Which of the following does NOT increase the rate of dissolving a solid in
water?
a. | raising the temperature | c. | using larger pieces of
solid | b. | stirring | d. | crushing the solid |
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11.
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Which of the following will dissolve most rapidly?
a. | sugar cubes in cold water | c. | powdered sugar in cold
water | b. | sugar cubes in hot water | d. | powdered sugar in hot water |
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12.
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Raising the collision rate between solute and solvent
a. | increases the rate of dissolution. | b. | decreases the rate of
dissolution. | c. | has no effect on the rate of dissolution. | d. | can increase,
decrease, or have no effect on the rate of dissolution. |
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13.
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If the amount of dissolved solute in a solution at a given temperature is
greater than the amount that can permanently remain in solution at that temperature, the solution is
said to be
a. | saturated. | c. | supersaturated. | b. | unsaturated. | d. | diluted. |
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14.
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The solubility of a substance at a given temperature can be expressed as
a. | grams of solute. | c. | amount of solute per amount of solvent. | b. | grams of
solvent. | d. | grams of water per
100 g of solute. |
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15.
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Which of the following is an example of a polar solvent?
a. | carbon tetrachloride | c. | water | b. | benzene | d. | gasoline |
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16.
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When the energy released by forming solvent-solute attractions is greater than
the energy absorbed by overcoming solute-solute and solvent-solvent attractions, the dissolving
process
a. | has a negative heat of solution. | c. | occurs rapidly. | b. | has a positive heat
of solution. | d. | does not
occur. |
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17.
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The formation of solid-liquid solutions
a. | always releases heat. | c. | can either absorb or release heat. | b. | always absorbs
heat. | d. | neither absorbs nor
releases heat. |
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18.
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Pressure has the greatest effect on the solubility of
a. | solids in liquids. | c. | gases in gases. | b. | liquids in liquids. | d. | gases in
liquids. |
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19.
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The solubility of gases in liquids
a. | always increases with increasing pressure. | b. | sometimes increases
with increasing pressure. | c. | always decreases with increasing
pressure. | d. | does not depend on pressure. |
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20.
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For a mixture of gases, the solubility of each gas in water varies
a. | directly with the partial pressure of the gas. | b. | inversely with the
partial pressure of the gas. | c. | directly with the total pressure of the
mixture. | d. | inversely with the total pressure of the mixture. |
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21.
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As temperature increases, solubility of gases in liquids
a. | increases. | c. | can increase or decrease. | b. | decreases. | d. | is not affected. |
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22.
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What is the molality of a solution that contains 5.10 mol KNO3 in
4.47 kg water?
a. | 0.315 m | c. | 1.02 m | b. | 0.779 m | d. | 1.14 m |
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23.
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How many moles of HCl are present in 0.70 L of a 0.33 M HCl solution?
a. | 0.23 mol | c. | 0.38 mol | b. | 0.28 mol | d. | 0.47 mol |
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24.
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The concentration of a water solution of NaCl is 2.48 m, and it contains
806 g of water. How much NaCl is in the solution?
a. | 2.00 g | c. | 117 g | b. | 89.3 g | d. | 224 g |
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25.
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An NaOH solution contains 1.90 mol of NaOH, and its concentration is 0.555 M.
What is its volume?
a. | 0.623 L | c. | 1.05 L | b. | 0.911 L | d. | 3.42 L |
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26.
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When solutions of two ionic compounds are combined and a solid forms, the
process is called
a. | hydration. | c. | solvation. | b. | precipitation. | d. | dissociation. |
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27.
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The attraction of water molecules overcomes the strength of covalent bonds
in
a. | all molecular substances. | b. | molecular substances that are
electrolytes. | c. | molecular substances that are not electrolytes. | d. | none of the
above |
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28.
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The separation of ions that occurs when an ionic compound dissolves is
called
a. | ionization. | c. | precipitaion. | b. | dissociation. | d. | oxidation. |
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29.
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When a molecular substance ionizes in water,
a. | charged particles are formed and the more electronegative atom becomes a negative
ion. | b. | charged particles are formed and the less electronegative atom becomes a negative
ion. | c. | no charged particles are formed. | d. | ions that were already present are
released. |
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30.
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A compound of low solubility
a. | is always a strong electrolyte. | c. | may be a strong or a weak
electrolyte. | b. | is always a weak electrolyte. | d. | is always a
nonelectrolyte. |
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