Question 1

A passage of substance directly from the vapor to the solid state is known as:

Accepted Answer

A)  deposition 
B)  decomposition 
C)  sublimation 
D)  solidification 
E)  fusion

Question 2

The phenomenon of supercooling refers to the existence of a metastable:

Accepted Answer

A)  liquid at a temperature below that of its critical point 
B)  liquid at a temperature below that of its sublimation point 
C)  liquid at a temperature below that of its freezing point 
D)  gas at a temperature below that of its critical point 
E)  two-phase liquid/solid mixture at the freezing point

Question 3

Choose the INCORRECT statement.

Accepted Answer

A)  In a network covalent solid, covalent bonds extend throughout the crystalline solid. 
B)  Diamond has sp3 hybridization. 
C)  Graphite has sp hybridization. 
D)  Fullarenes are a recently discovered allotropic form of carbons. 
E)  Nanotubes are an allotropic form of carbon.

Question 4

If a substance has a heat of condensation of -1.46 kJ/g and a heat of sublimation of 4.60 kJ/g, what is its heat of solidification in kJ/g?

Accepted Answer

A)  4.60 - 1.46 kJ/g 
B)  -(4.60 + 1.46) kJ/g 
C)  1.46 - 4.60 kJ/g 
D)  4.60 + 1.46 kJ/g 
E)  0 kJ/g

Question 5

The phenomenon in which a steel needle can, with proper care, be made to float on the surface of some water illustrates a property of liquids known as:

Accepted Answer

A)  compressibility 
B)  polarizability 
C)  surface tension 
D)  triple point 
E)  viscosity

Question 6

How much heat would be released by the condensation of 5.40 g of steam at 100°C and the subsequent cooling of the water to 25°C? [ΔHvap = 40.7 kJ/mol at 100°C; Cp for H2O(l) is 4.18 J g-1 °C-1]

Accepted Answer

A)  12.2 kJ 
B)  12.8 kJ 
C)  13.9 kJ 
D)  18.3 kJ 
E)  23.7 kJ

Question 7

When a liquid is in equilibrium with its vapor in a closed container:

Accepted Answer

A)  the rate at which molecules from the liquid phase enter the gas phase exactly equals the rate at which molecules from the gas phase pass into the liquid phase 
B)  a change in temperature will not change the pressure in the container 
C)  the amount of gas in the container must exactly equal the amount of liquid 
D)  molecules cannot go from the liquid phase to the gas phase because the amount of liquid in the container is constant 
E)  the vapor will gradually change back to the liquid state, that is, no vapor will be left

Question 8

What would be the appropriate equilibrium temperature of a system obtained by adding 25.0 g of ice at 0°C to 250.0 mL of "hot" (80°C) coffee, assuming that the heat capacity and density of the coffee are the same as for pure water (4.18 J g-1 °C-1 and 0.997 g mL-1), and also assuming negligible heat transfer with the surroundings? [For water, ΔHfusion = 6.02 kJ/mol.]

Accepted Answer

A)  33°C 
B)  40°C 
C)  65°C 
D)  73°C 
E)  79°C

Question 9

Given the data below, determine the molar enthalpy change of vaporization of liquid Rb. Rb, P1 = 1.00 mmHg, t1 = 297°C, P2 = 400 mmHg, t2 = 620°C

Accepted Answer

A)  5.49 kJ/mol 
B)  28.4 kJ/mol 
C)  78.5 kJ/mol 
D)  12.8 kJ/mol 
E)  4.62 kJ/mol

Question 10

Which probably has the lowest boiling point at 1.0 atm pressure?

Accepted Answer

A)  PbH4 
B)  SnH4 
C)  SiH4 
D)  GeH4 
E)  CH4

Question 11

The heat of deposition equals the negative of the heat of ________.

Accepted Answer

A)  fusion 
B)  condensation 
C)  sublimation 
D)  solidification 
E)  reposition

Question 12

Given the tabulated data, what is the lattice energy of crystalline calcium chloride? heat of sublimation for calcium +178 kJ/mol
First ionization energy for calcium +590 kJ/mol
Second ionization energy for calcium +1145 kJ/mol
Heat of dissociation for chlorine +122 kJ/mol(Cl)
Electron affinity for chlorine -349 kJ/mol
Heat of formation for calcium chloride -796 kJ/mol

Accepted Answer

A)  -1996 kJ/mol 
B)  -2101 kJ/mol 
C)  -2255 kJ/mol 
D)  -2345 kJ/mol 
E)  -2450 kJ/mol

Question 13

Liquid and vapor phases of a substance become indistinguishable at the ________.

Accepted Answer

A)  triple point 
B)  normal point 
C)  permanent point 
D)  critical point 
E)  absolute point

Question 14

An arrangement in which every other layer is identical (ABABABAB) is ________.

Accepted Answer

A)  octahedral holes 
B)  tetrahedral holes 
C)  hexagonal close packed 
D)  cubic close packing 
E)  cubic face centered

Question 15

Which combination of "type of solid" and specific example is INCORRECT?

Accepted Answer

A)  ionic/"table salt" 
B)  metallic/copper wire 
C)  molecular/"dry ice" 
D)  network covalent/iodine 
E)  network covalent/silicon carbide

Question 16

The triple point of H2O is at 4.58 mmHg and +0.01°C. Some H2O at -50°C is heated to 120°C at a constant pressure of 0.5 atm. The changes of state occurring in this process are:

Accepted Answer

A)  solid to gas 
B)  solid to liquid to gas 
C)  liquid to gas 
D)  solid to liquid 
E)  gas to liquid to solid

Question 17

When a liquid is in dynamic equilibrium with its vapor at a given temperature, the following conditions could exist: I) There is no transfer of molecules between liquid and vapor.
II) The vapor pressure has a unique value.
III) The opposing processes, (liquid to vapor) and (vapor to liquid), proceed at equal rates.
IV) The concentration of vapor is dependent on time.
Which of the above choices are applicable?

Accepted Answer

A)  I 
B)  II and III 
C)  I, II, and III 
D)  II and IV 
E)  II, III and IV

Question 18

Surface tension of a liquid is the work or energy required to increase the surface area of a liquid

Accepted Answer

A) True 
 B)False

Question 19

The process in which a gas is transformed into a solid is called ________.

Accepted Answer

A)  vaporization 
B)  condensation 
C)  solidification 
D)  deposition 
E)  fusion

Question 20

The property of a liquid that measures its resistance to flow is called ________.

Accepted Answer

A)  capillarity 
B)  polarizability 
C)  resistivity 
D)  viscosity 
E)  wetability

Exam 12: Intermolecular Forces: Liquids and Solids