NAME:
Ch 15 Water & AQ Systems
Period:
STUDY GUIDE
/69
Matching
Match each item with the correct statement below.
A. solvation
E. electrolyte
B. weak electrolyte
F. colloid
C. aqueous solution
G. surfactant
D. solvent
____
____
____
____
____
____
____
1.
2.
3.
4.
5.
6.
7.
interferes with hydrogen bonding between water molecules
dissolving medium
homogeneous mixture of water and dissolved substances
Solute ions or molecules are surrounded by solvent molecules.
compound that will conduct current in the liquid state or in aqueous solution
compound that ionizes incompletely in aqueous solution
mixture in which particle size averages between 1 nm and 1000 nm
Match each item with the correct statement below.
A. dispersed phase
E. Tyndall effect
B. surface tension
F. suspension
C. Brownian motion
G. solute
D. dispersion medium
H. emulsion
____
____
____
____
____
____
____
8.
9.
10.
11.
12.
13.
14.
inward force tending to minimize surface area of a liquid
dissolved particle
mixture in which particle size averages greater that 1000 nm in diameter
Colloidal particles spread throughout a suspension.
phenomenon observed when beam of light passes through a colloid
chaotic movement of colloidal particles
colloid of a liquid in a liquid
Multiple Choice
Identify the choice that best completes the statement or answers the question.
____ 15. How does the surface tension of water compare with the surface tensions of most other liquids?
A. It is lower.
B. It is about the same.
C. It is higher.
D. It is higher only when a surfactant is added.
____ 16. What causes water's low vapor pressure?
A. dispersion forces
C. hydrogen bonding
B. covalent bonding
D. ionic attractions
____ 17. What is the shape of the water molecule?
A. linear
B. tetrahedral
C. trigonal planar
D. bent
____ 18. Which of the following is primarily responsible for holding water molecules together in the liquid state?
____ 19.
____ 20.
____ 21.
____ 22.
____ 23.
____ 24.
____ 25.
____ 26.
____ 27.
____ 28.
____ 29.
____ 30.
A. dispersion forces
C. ionic bonds
B. hydrogen bonds
D. polar covalent bonds
Which atom in a water molecule has the greatest electronegativity?
A. one of the hydrogen atoms
B. both hydrogen atoms
C. the oxygen atom
D. There is no difference in the electronegativities of the atoms in a water molecule.
The bonds between adjacent water molecules are called ____.
A. hydrogen bonds
C. nonpolar covalent bonds
B. ionic bonds
D. polar covalent bonds
What is primarily responsible for the surface tension of water?
A. dispersion forces
C. ionic attractions
B. hydrogen bonding
D. covalent bonding
Which of the following is one of the effects of the high surface tension of water?
A. Surface area of water is maximized.
B. Water has an unusually low vapor pressure.
C. Materials are not impeded as they pass through the surface.
D. Falling drops tend to have rounded bottoms and pointed tops.
Which of these is a correct observation about surface tension?
A. It is the inward force which tends to minimize the surface area of a liquid.
B. It is the outward force which tends to maximize the surface area of a liquid.
C. It is decreased by hydrogen bonding.
D. It causes beads of water to spread out on a surface.
The bonds between the hydrogen and oxygen atoms in a water molecule are ____.
A. hydrogen bonds
C. nonpolar covalent bonds
B. ionic bonds
D. polar covalent bonds
How much heat is absorbed when 6.30 g of water melts?
A. 21 kJ
B. 0.210 kJ
C. 2.10 kJ
D. 21.0 J
The fact that ice is less dense than water is related to the fact that ____.
A. the molecular structure of ice is much less orderly than that of water
B. the molecules of ice are held to each other by covalent bonding
C. ice has a molecular structure in which water molecules are arranged randomly
D. ice has a molecular structure that is an open framework held together by hydrogen
bonds
Which is responsible for the high thermal energy required to melt ice?
A. covalent bonding
C. hydrogen bonding
B. dispersion forces
D. ionic attractions
What is the term for the dissolving medium in a solution?
A. solvent
B. solute
C. solvator
D. emulsifier
A solution has which of the following properties?
A. Gravity separates its parts.
B. The top layer is different in composition than the bottom layer.
C. The average diameter of its solute particles usually is less than 1 nm.
D. A filter can remove the solute.
Which of the following substances is the most soluble in water?
A. sodium chloride B. methane
C. bromine
D. carbon
____ 31. What occurs in solvation?
A. Solute ions separate from solvent molecules.
B. Solvent molecules surround solute ions.
C. Solvent molecules bind covalently to solute molecules.
D. Ionic compounds are formed.
____ 32. Which of the following substances dissolves most readily in gasoline?
A. CH
B. HCl
C. NH
D. NaBr
____ 33. A solution is a mixture
A. from which the solute can be filtered.
B. that has the same properties throughout.
C. that is heterogeneous.
D. in which a solid solute is always dissolved in a liquid solvent.
____ 34. Which of these compounds is likely to have very low solubility in water?
A. NaCl
B. HCl
C. CF
D. CuSO
____ 35. Why is a nonpolar substance able to dissolve a different nonpolar substance?
A. They have similar attractive forces in their molecules.
B. They combine to produce a polar substance.
C. There is no attractive force between them.
D. Nonpolar substances cannot dissolve in each other.
____ 36. Which compound would you expect to be soluble in the nonpolar solvent carbon disulfide?
A.
B. CI
C. NaCl
D. SnS
____ 37. Which compound dissolves most readily in water?
A. BaSO
B. CaCO
C. NH
D. CH
____ 38. What type of compound is always an electrolyte?
A. polar covalent
C. ionic
B. nonpolar covalent
D. network solid
____ 39. An electric current can be best conducted by ____.
A. methane gas
B. a sugar solution
C. a salt solution
D. rubbing alcohol
____ 40. Which of the following compounds conducts electricity only in the molten state?
A. sodium bromide
C. calcium hydroxide
B. magnesium sulfate
D. barium sulfate
____ 41. Which of the following compounds is a nonelectrolyte?
A. sodium bromide
C. copper chloride
B. magnesium sulfate
D. carbon tetrachloride
____ 42. Which of the following compounds is an electrolyte in aqueous solution?
A. methanol
C. carbon tetrachloride
B. sugar
D. sodium hydroxide
____ 43. Which of the following compounds is a nonelectrolyte when pure, but an electrolyte when dissolved in
water?
A. 2-propanol
C. carbon tetrachloride
B. sucrose
D. ammonia
____ 44. Which of the following are weak electrolytes in water?
A. ionic compounds that partially dissociate in water
B. ionic compounds that are soluble
C. polar compounds that ionize
D. nonpolar compounds that do not ionize
____ 45. Which of the following compounds is a weak electrolyte?
A. NaBr
B. HBr
C. KOH
D. NH
____ 46. Which of the following compounds is a strong electrolyte?
A. ammonia
C. sucrose
B. acetic acid
D. potassium sulfate
____ 47. Which of the following substances is an electrolyte?
A. CH
B. CCl
C. Cl2
D. MgCl2
____ 48. Which of these materials is a hydrate?
A. baking soda
B. saltwater
C. Epsom salt
D. sugar
____ 49. Which symbol is used to connect the formula of the compound with the number of water molecules in a
hydrate?
A. a parenthesis
C. a multiplication symbol
B. an asterisk
D. a dot
____ 50. What is another term for the water of hydration?
A. water of solvation
C. water of sublimation
B. water of crystallization
D. water of efflorescence
____ 51. Which compound changes color when it becomes a hydrate?
A. silicon dioxide
C. copper(II) sulfate
B. sodium chloride
D. potassium chloride
____ 52. The term that describes a hydrated crystal that has a water vapor pressure greater than the water vapor
pressure of air is ____.
A. desiccant
B. deliquescent
C. hygroscopic
D. efflorescent
____ 53. A crystal that absorbs water vapor from the air is ____.
A. aqueous
B. deliquescent
C. hygroscopic
D. efflorescent
____ 54. Which of the following mixture types is characterized by the settling of particles?
A. solution
B. suspension
C. colloid
D. hydrate
____ 55. Which of the following mixture types can be filtered to remove solute?
A. suspensions only
C. suspensions and colloids
B. colloids only
D. suspensions and solutions
____ 56. Which of the following materials is a colloid?
A. gasoline
B. bronze
C. smoke
D. vinegar
____ 57. Which of the following mixtures is a colloid?
A. air
B. milk
C. tap water
D. sugar water
____ 58. An emulsion is which type of mixture?
A. suspension
B. colloid
C. solution
D. gaseous
____ 59. The solute in a colloidal suspension is designated as the _______.
A. dissolving phase
C. dispensing phase
B. dispersed phase
D. dispersion medium
____ 60. What is the size range of particles in a colloid?
A. more than 1000 nm
C. between 1 nm and 1000 nm
B. between 100 nm and 1000 nm
D. between 1 nm and 10 nm
____ 61. Which of these materials is an emulsion?
____ 62.
____ 63.
____ 64.
____ 65.
A. gelatin
B. milk
C. paint
D. saltwater
Which of these statements is correct?
A. Particles can be filtered from a suspension.
B. A solution is heterogeneous.
C. A colloidal system does not exhibit the Tyndall effect.
D. The particles in a colloidal system are affected by gravity.
An emulsion is a colloidal dispersion of a ____
A. solid in a liquid.
B. liquid in a liquid. C. gas in a liquid.
D. liquid in a gas.
An emulsifying agent is typically characterized by having ____.
A. one polar end
C. two polar ends
B. one nonpolar end
D. one polar end and one nonpolar end
What causes Brownian motion in colloids?
A. collisions between particles of the dispersed phase and the dispersion medium
B. coagulation and settling of particles of the dispersed phase
C. absorption of energy from light resulting from the dispersed phase
D. variation in particle sizes within the colloid
Numeric Response
66. How many hydrogen bonds can be formed between one hydrogen atom in a water molecule and oxygen
atoms of surrounding water molecules?
67. How many nonbonding pairs of electrons are in a water molecule?
68. How many water molecules are in 39 formula units of calcium chloride dihydrate (CaCl2
2H2O)?
69. If all of the water is removed from a one mole sample of Ba(OH)2·8H2O, by how many grams will the mass of
the sample be reduced?