Chapter 10: Liquids and Solids

	1.	Order the intermolecular forces (dipole-dipole, London dispersion, ionic, and hydrogen-bonding) from weakest to strongest .
A)	dipole-dipole, London dispersion, ionic, and hydrogen-bonding	
B)	London dispersion, dipole-dipole, hydrogen-bonding, and ionic	
C)	hydrogen-bonding, dipole-dipole, London dispersion, and ionic	
D)	dipole-dipole, ionic, London dispersion, and hydrogen-bonding	
E)	London dispersion, ionic, dipole-dipole, and hydrogen-bonding	

ANS:	B	PTS:	1	DIF:	Easy	REF:	10.1
KEY:	Chemistry | general chemistry | phases | intermolecular forces |	
MSC:	Conceptual

	2.	Hydrogen bonds account for which of the following observation?
A)	Hydrogen naturally exists as a diatomic molecule.	
B)	Hydrogen is easily combustible with oxygen.	
C)	Water molecules are bent or "V-shaped."	
D)	Air is more dense than hydrogen gas.	
E)	For its molar mass, water has a high boiling point.	

ANS:	E	PTS:	1	DIF:	Easy	REF:	10.1
KEY:	Chemistry | general chemistry | phases | intermolecular forces | hydrogen bonds
MSC:	Conceptual

	3.	Which of the following would you expect to have the highest boiling point?
A)	F2	
B)	Cl2	
C)	Br2	
D)	I2	
E)	All of the above have the same boiling point.	

ANS:	D	PTS:	1	DIF:	Easy	REF:	10.1
KEY:	Chemistry | general chemistry | phases | liquid | intermolecular forces
MSC:	Conceptual

	4.	Which of the following should have the lowest boiling point?
A)	Na2S	
B)	HF	
C)	NH3	
D)	N2	
E)	H2O	

ANS:	D	PTS:	1	DIF:	Easy	REF:	10.1
KEY:	Chemistry | general chemistry | phases | liquid | intermolecular forces
MSC:	Conceptual

	5.	Which of the species below would you expect to show the least hydrogen bonding?
A)	NH3	
B)	H2O	
C)	HF	
D)	CH4	
E)	all the same	

ANS:	D	PTS:	1	DIF:	Moderate	REF:	10.1
KEY:	Chemistry | general chemistry | phases | intermolecular forces | hydrogen bonds
MSC:	Conceptual

	6.	The molecules in a sample of solid SO2 are attracted to each other by a combination of
A)	London forces and H-bonding	
B)	H-bonding and ionic bonding	
C)	covalent bonding and dipole-dipole interactions	
D)	London forces and dipole-dipole interactions	
E)	none of these	

ANS:	D	PTS:	1	DIF:	Easy	REF:	10.1
KEY:	Chemistry | general chemistry | phases |  intermolecular forces	
MSC:	Conceptual

	7.	In which of the following groups of substances would dispersion forces be the only significant factors in determining boiling points?
I.	Cl2	II.	HF	III.	Ne	IV.	KNO2	V.	CCl4	

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

ANS:	A	PTS:	1	DIF:	Easy	REF:	10.1
KEY:	Chemistry | general chemistry | phases | liquid | intermolecular forces | London forces
MSC:	Conceptual

	8.	The elements of group 5A, the nitrogen family, form compounds with hydrogen having the boiling points listed below:
          SbH3 –17°C,  AsH3 –55°C,  PH3 –87°C,  NH3 –33°C
The first three compounds illustrate a trend where the boiling point decreases as the mass decreases; however, ammonia (NH3) does not follow the trend because of
A)	dipole-dipole attraction	
B)	metallic bonding	
C)	hydrogen bonding	
D)	London dispersion forces	
E)	ionic bonding	

ANS:	C	PTS:	1	DIF:	Easy	REF:	10.1
KEY:	Chemistry | general chemistry | phases | liquid | intermolecular forces
MSC:	Conceptual

	9.	Which substance involves no bonding forces except London dispersion forces?
A)	NaCl(l)	
B)	HF(l)	
C)	N2(s)	
D)	H2O(l)	
E)	K(s)	

ANS:	C	PTS:	1	DIF:	Easy	REF:	10.1
KEY:	Chemistry | general chemistry | phases | intermolecular forces | London forces
MSC:	Conceptual

	10.	In general, the density of a compound as a gas is closer in value to that of the compound as a liquid than the density of the compound as a liquid is in value to that of the compound as a solid.

ANS:	F	PTS:	1	DIF:	Easy	REF:	10.1
KEY:	Chemistry | general chemistry | phases		MSC:	Conceptual

	11.	Second row hydrides generally have higher than expected boiling points for their position on the periodic table.

ANS:	T	PTS:	1	DIF:	Easy	REF:	10.1
KEY:	Chemistry | general chemistry | phases | liquid | intermolecular forces
MSC:	Conceptual

	12.	The bonds between hydrogen and oxygen within a water molecule can be characterized as __________.
A)	hydrogen bonds	
B)	London dispersion forces	
C)	intermolecular forces	
D)	intramolecular forces	
E)	dispersion forces	

ANS:	D	PTS:	1	DIF:	Easy	REF:	10.1
KEY:	Chemistry | general chemistry | phases | intermolecular forces | hydrogen bonds
MSC:	Conceptual

	13.	When a water molecule forms a hydrogen bond with another water molecule, which atoms are involved in the interaction?
A)	a hydrogen from one molecule and a hydrogen from the other molecule	
B)	a hydrogen from one molecule and an oxygen from the other molecule	
C)	an oxygen from one molecule and an oxygen from the other molecule	
D)	an oxygen and a hydrogen from the same molecule	
E)	two hydrogens from one molecule and one hydrogen from the other molecule	

ANS:	B	PTS:	1	DIF:	Easy	REF:	10.1
KEY:	Chemistry | general chemistry | phases | intermolecular forces | hydrogen bonding
MSC:	Conceptual

	14.	Which of the following is the correct order of boiling points for KNO3, CH3OH, C2H6, Ne?
A)	Ne < CH3OH < C2H6 < KNO3	
B)	KNO3 < CH3OH < C2H6 < Ne	
C)	Ne < C2H6 < KNO3 < CH3OH	
D)	Ne < C2H6 < CH3OH < KNO3	
E)	C2H6 < Ne < CH3OH < KNO3	

ANS:	D	PTS:	1	DIF:	Moderate	REF:	10.1
KEY:	Chemistry | general chemistry | phases | liquid	MSC:	Conceptual

Consider the representations below to answer the next three questions.
(I)

(II)

(III)

	15.	How many of the following statements are correct concerning drawing I?
 I.	Each molecule induces a dipole onto the next molecule in close proximity.	
II.	The phenomenon shown is relatively weak and short-lived.	
III.	C8H18 contains this type of interaction. 	
IV.	The forces that exist in this example are London dispersion forces.	

A)	0	
B)	1	
C)	2	
D)	3	
E)	4	

ANS:	E	PTS:	1	DIF:	Moderate	REF:	10.1
KEY:	Chemistry | general chemistry | phases |  intermolecular forces | London forces
MSC:	Conceptual

	16.	Which drawing best represents the interactions in a sample of HF?
A)	I	
B)	II	
C)	III	
D)	I, II	
E)	all of the above	

ANS:	B	PTS:	1	DIF:	Easy	REF:	10.1
KEY:	Chemistry | general chemistry | phases | intermolecular forces | hydrogen bonding
MSC:	Conceptual

	17.	Which of the following statements are incorrect concerning drawing III?
A)	Electrostatic interactions exist between the molecules.	
B)	The molecules find the best compromise between attraction and repulsion.	
C)	These molecules exhibit ionic bonding.	
D)	OCS exhibits this type of interaction.	
E)	Two of the above statements are incorrect.	

ANS:	C	PTS:	1	DIF:	Easy	REF:	10.1
KEY:	Chemistry | general chemistry | phases | intermolecular forces	
MSC:	Conceptual

	18.	The freezing point of helium is –270°C. The freezing point of xenon is –112°C. Both of these are in the noble gas family. Which of the following statements is supported by these data?
A)	Helium and xenon form highly polar molecules.	
B)	As the molecular weight of the noble gas increases, the freezing point decreases.	
C)	The London dispersion forces between the helium molecules are greater than the London dispersion between the xenon molecules.	
D)	The London dispersion forces between the helium molecules are less than the London dispersion forces between the xenon molecules.	
E)	None of these.	

ANS:	D	PTS:	1	DIF:	Easy	REF:	10.1
KEY:	Chemistry | general chemistry | phases | liquid | intermolecular forces
MSC:	Conceptual

	19.	Which best explains the following trend?
Element	b.p. (K)	
He	4	
Ne	25	
Ar	95	
Kr	125	
Xe	170	

A)	London dispersion forces	
B)	dipole-dipole interaction	
C)	hydrogen bonding	
D)	Le Chatelier's principle	
E)	none of these	

ANS:	A	PTS:	1	DIF:	Easy	REF:	10.1
KEY:	Chemistry | general chemistry | phases | liquid | intermolecular forces | London forces
MSC:	Conceptual

	20.	Intermolecular forces are weaker than intramolecular bonds.

ANS:	T	PTS:	1	DIF:	Easy	REF:	10.1
KEY:	Chemistry | general chemistry | phases | intermolecular forces	
MSC:	Conceptual

	21.	Hydrogen bonding is a type of London dispersion force.

ANS:	F	PTS:	1	DIF:	Easy	REF:	10.1
KEY:	Chemistry | general chemistry | phases |  intermolecular forces | hydrogen bonding
MSC:	Conceptual

	22.	Methane (CH4) exhibits stronger hydrogen bond interactions than ammonia (NH3).

ANS:	F	PTS:	1	DIF:	Easy	REF:	10.1
KEY:	Chemistry | general chemistry | phases | intermolecular forces | hydrogen bonding
MSC:	Conceptual

	23.	Which of the following compounds has the lowest viscosity?
A)	CCl4(l)	
B)	N2(g)	
C)	H2O(l)	
D)	CH3-(CH2)25-CH3(l)	
E)	HCl(g)	

ANS:	B	PTS:	1	DIF:	Easy	REF:	10.2
KEY:	Chemistry | general chemistry | phases | liquid | properties of liquids | viscosity
MSC:	Conceptual

	24.	Which of the following statements about liquids is true?
A)	Droplet formation occurs because of the higher stability associated with increased surface area.	
B)	Substances that can form hydrogen bonds will display lower melting points than predicted from periodic trends.	
C)	London dispersion forces arise from a distortion of the electron clouds within a molecule or atom.	
D)	Liquid rise within a capillary tube because of the small size lowers the effective atmospheric pressure over the surface of the liquid.	
E)	The boiling point of a solution is dependent solely on the atmospheric pressure over the solution.	

ANS:	C	PTS:	1	DIF:	Easy	REF:	10.2
KEY:	Chemistry | general chemistry | phases | liquid | properties of liquids
MSC:	Conceptual

	25.	What is responsible for capillary action, a property of liquids?
A)	surface tension	
B)	cohesive forces	
C)	adhesive forces	
D)	viscosity	
E)	two of these	

ANS:	E	PTS:	1	DIF:	Easy	REF:	10.2
KEY:	Chemistry | general chemistry | phases | liquid | properties of liquids
MSC:	Conceptual

	26.	When a nonpolar liquid displays a convex meniscus, which of the following explains this behavior?
A)	It has a low surface tension, and therefore clings to the glass.	
B)	The cohesive forces are stronger than the adhesive forces to the glass.	
C)	The adhesive forces to the glass are stronger than the cohesive forces.	
D)	The liquid's viscosity is low.	
E)	None of these.	

ANS:	B	PTS:	1	DIF:	Easy	REF:	10.2
KEY:	Chemistry | general chemistry | phases | liquid | properties of liquids
MSC:	Conceptual

	27.	Liquids with large intermolecular forces tend to have high surface tension.

ANS:	T	PTS:	1	DIF:	Easy	REF:	10.2
KEY:	Chemistry | general chemistry | phases | liquid | properties of liquids | surface tension
MSC:	Conceptual

	28.	The unit cell in this two-dimensional crystal contains __________ Xs and __________ Os.
	X	X	X	X	
	O	O	O	O	
	X	X	X	X	
	O	O	O	O	
	X	X	X	X	
	O	O	O	O	

A)	1,1	
B)	2,1	
C)	1,2	
D)	4,1	
E)	1,4	

ANS:	A	PTS:	1	DIF:	Easy	REF:	10.3
KEY:	Chemistry | general chemistry | phases | solid | crystalline solids | crystal lattice
MSC:	Conceptual

	29.	Which of the following is paired incorrectly?
A)	crystalline solids—highly regular arrangement of their components	
B)	amorphous solids—considerable disorder in their structures	
C)	unit cell—the smallest repeating unit of the lattice	
D)	gold metal—simple cubic unit cell	
E)	glass—amorphous solid	

ANS:	D	PTS:	1	DIF:	Easy	REF:	10.3
KEY:	Chemistry | general chemistry | phases | solid | classification of solids
MSC:	Conceptual

	30.	Table salt and table sugar are both crystalline solids.

ANS:	T	PTS:	1	DIF:	Easy	REF:	10.3
KEY:	Chemistry | general chemistry | phases | solid | crystalline solids	
MSC:	Conceptual

	31.	Atomic solids generally have low melting points.

ANS:	F	PTS:	1	DIF:	Moderate	REF:	10.3
KEY:	Chemistry | general chemistry | phases | solid | classification of solids
MSC:	Conceptual

	32.	A crystal was analyzed with x-rays having 1.57 Å wavelength. A reflection was produced at q = 21.9°. Assuming n = 1, what is the distance between the layers of atoms in the crystal?
A)	8.42 Å	
B)	4.21 Å	
C)	0.475 Å	
D)	0.846 Å	
E)	2.10 Å	

ANS:	E	PTS:	1	DIF:	Moderate	REF:	10.3
KEY:	Chemistry | general chemistry | phases | solid | x-ray diffraction	
MSC:	Quantitative

	33.	A crystal was analyzed with x-rays having 2.33 Å wavelength. The angle of first-order diffraction (n = 1) was 19.2°. What would be the angle for second-order diffraction (n = 2)?
A)	38.4 Å	
B)	41.1 Å	
C)	9.46 Å	
D)	14.2 Å	
E)	4.72 Å	

ANS:	B	PTS:	1	DIF:	Difficult	REF:	10.3
KEY:	Chemistry | general chemistry | phases | solid | x-ray diffraction	
MSC:	Quantitative

The molar volume of a certain form of solid lead is 18 cm3/mol. Assuming cubic closest packed structure, determine the following:

	34.	The number of Pb atoms per unit cell.
A)	1	
B)	2	
C)	4	
D)	6	
E)	10	

ANS:	C	PTS:	1	DIF:	Moderate	REF:	10.4
KEY:	Chemistry | general chemistry | phases | solid | calculations with unit cell dimensions
MSC:	Quantitative

	35.	The volume of a single cell.
A)	1.20 ´ 102 pm3	
B)	1.20 ´ 104 pm3	
C)	1.20 ´ 106 pm3	
D)	1.20 ´ 108 pm3	
E)	none of these	

ANS:	D	PTS:	1	DIF:	Moderate	REF:	10.4
KEY:	Chemistry | general chemistry | phases | solid | calculations with unit cell dimensions
MSC:	Quantitative

	36.	The radius of a Pb atom.
A)	1.74 pm	
B)	17.4 pm	
C)	174 pm	
D)	1740 pm	
E)	none of these	

ANS:	C	PTS:	1	DIF:	Moderate	REF:	10.4
KEY:	Chemistry | general chemistry | phases | solid | calculations with unit cell dimensions
MSC:	Quantitative

	37.	Cubic closest packing is another name for _____________.
A)	simple cubic packing	
B)	body-centered cubic packing	
C)	face-centered cubic packing	
D)	hexagonal closest packing	
E)	more than one of these	

ANS:	C	PTS:	1	DIF:	Moderate	REF:	10.4
KEY:	Chemistry | general chemistry | phases | solid | crystalline solids | cubic unit cell
MSC:	Conceptual

	38.	Which one of the following statements about solid Cu (face-centered cubic unit cell) is incorrect?
A)	It will conduct electricity.	
B)	There are two atoms per unit cell.	
C)	The number of atoms surrounding each Cu atom is 12.	
D)	The solid has a cubic closest-packed structure.	
E)	The length of a face diagonal is four times the Cu radius.	

ANS:	B	PTS:	1	DIF:	Moderate	REF:	10.4
KEY:	Chemistry | general chemistry | phases | solid | crystalline solids | cubic unit cell
MSC:	Conceptual

	39.	In any cubic lattice an atom lying at the corner of a unit cell is shared equally by how many unit cells?
A)	1	
B)	4	
C)	8	
D)	2	
E)	6	

ANS:	C	PTS:	1	DIF:	Easy	REF:	10.4
KEY:	Chemistry | general chemistry | phases | solid | crystalline solids | cubic unit cell
MSC:	Conceptual

	40.	Which of the following statements is (are) false?
 I.	The layering in a hexagonal closest-packed structure is aba.	
II.	A body-centered cubic unit cell has four atoms per unit cell.	
III.	For unit cells having the same edge length, a simple cubic structure would have a smaller density than a body-centered cube.	
IV.	Atoms in a solid consisting of only one element would have six nearest neighbors if the crystal structure were a simple cubic array.	

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

ANS:	B	PTS:	1	DIF:	Moderate	REF:	10.4
KEY:	Chemistry | general chemistry | phases | solid	MSC:	Conceptual

	41.	Aluminum metal crystallizes in a face-centered cubic structure. The relationship between the radius of an Al atom (r) and the length of an edge of the unit cell (E) is:
A)	r = E/2	
B)		
C)		
D)	r = 2E	
E)		

ANS:	B	PTS:	1	DIF:	Easy	REF:	10.4
KEY:	Chemistry | general chemistry | phases | solid | crystalline solids | cubic unit cell
MSC:	Conceptual

	42.	Chromium metal crystallizes as a body-centered cubic lattice. If the atomic radius of Cr is 1.25 angstroms, what is the density of Cr metal in g/cm3?
A)	5.52	
B)	7.18	
C)	14.4	
D)	2.76	
E)	3.59	

ANS:	B	PTS:	1	DIF:	Difficult	REF:	10.4
KEY:	Chemistry | general chemistry | phases | solid | calculations with unit cell dimensions
MSC:	Quantitative

	43.	You are given a small bar of an unknown metal, M. You find the density of the metal to be 10.5 g/cm3. An X-ray diffraction experiment measures the edge of the unit cell as 409 pm. Assuming that the metal crystallizes in a face-centered cubic lattice, what is M most likely to be?
A)	Ag	
B)	Rh	
C)	Pt	
D)	Pb	
E)	none of these	

ANS:	A	PTS:	1	DIF:	Difficult	REF:	10.4
KEY:	Chemistry | general chemistry | phases | solid | calculations with unit cell dimensions
MSC:	Quantitative

	44.	Silver chloride crystallizes with the sodium chloride (rock salt) structure. The length of a unit cell edge is 555 pm. What is the density of AgCl?
A)	5.57 g/cm3	
B)	4.19 g/cm3	
C)	2.79 g/cm3	
D)	2.10 g/cm3	
E)	1.39 g/cm3	

ANS:	A	PTS:	1	DIF:	Moderate	REF:	10.4
KEY:	Chemistry | general chemistry | phases | solid | calculations with unit cell dimensions
MSC:	Quantitative

	45.	A metal crystallizes in a body-centered unit cell with an edge length of 2.00 ´ 102 pm. Assume the atoms in the cell touch along the cube diagonal. The percentage of empty volume in the unit cell will be:
A)	0%	
B)	26.0%	
C)	32.0%	
D)	68.0%	
E)	none of these	

ANS:	C	PTS:	1	DIF:	Difficult	REF:	10.4
KEY:	Chemistry | general chemistry | phases | solid | calculations with unit cell dimensions
MSC:	Quantitative

	46.	A metal crystallizes with a face-centered cubic lattice. The edge of the unit cell is 395 pm. The diameter of the metal atom is:
A)	140 pm	
B)	198 pm	
C)	279 pm	
D)	395 pm	
E)	none of these	

ANS:	C	PTS:	1	DIF:	Moderate	REF:	10.4
KEY:	Chemistry | general chemistry | phases | solid | calculations with unit cell dimensions
MSC:	Quantitative

	47.	If equal, rigid spheres are arranged in a simple cubic lattice in the usual way (i.e., in such a way that they touch each other), what fraction of the corresponding solid will be empty space? [The volume of a sphere is (4/3)pr3, with p = 3.14.]
A)	0.52	
B)	0.32	
C)	0.68	
D)	0.48	
E)	none of these	

ANS:	D	PTS:	1	DIF:	Difficult	REF:	10.4
KEY:	Chemistry | general chemistry | phases | solid | calculations with unit cell dimensions
MSC:	Quantitative

	48.	Which substance can be described as cations bonded together by mobile electrons?
A)	Ag(s)	
B)	S8(s)	
C)	Kr(l)	
D)	KCl(s)	
E)	HCl(l)	

ANS:	A	PTS:	1	DIF:	Easy	REF:	10.4
KEY:	Chemistry | general chemistry | phases | solid | classification of solids
MSC:	Conceptual

	49.	Steel is considered to be a(n) __________.
A)	interstitial alloy	
B)	ionic solid	
C)	molecular solid	
D)	substitutional alloy	
E)	two of these	

ANS:	A	PTS:	1	DIF:	Easy	REF:	10.4
KEY:	Chemistry | general chemistry | materials chemistry | metal		
MSC:	Conceptual

	50.	Which of the following statements about steel is false?
A)	It contains carbon atoms in the holes of its iron crystals.	
B)	The presence of carbon-iron bonds in the alloy make steel harder and stronger than pure iron.	
C)	Pure iron is relatively soft and ductile because it lacks directional bonding.	
D)	The amount of carbon directly affects the properties of steel.	
E)	All of these are true.	

ANS:	E	PTS:	1	DIF:	Easy	REF:	10.4
KEY:	Chemistry | general chemistry | materials chemistry | metal		
MSC:	Conceptual

	51.	What is the simplest formula of a solid containing A, B, and C atoms in a cubic lattice in which the A atoms occupy the corners, the B atoms the body-center position, and the C atoms the faces of the unit cell?
A)	ABC	
B)	ABC3	
C)	ABC6	
D)	A8BC6	
E)	A4BC3	

ANS:	B	PTS:	1	DIF:	Easy	REF:	10.4
KEY:	Chemistry | general chemistry | phases | solid | crystalline solids | cubic unit cell
MSC:	Conceptual

	52.	A solid material consists of an array of A atoms with Z atoms located in the spaces in the lattice. This solid would be classified as
A)	an amalgam	
B)	an interstitial alloy	
C)	a substitutional alloy	
D)	a semiconductor	
E)	ceramic	

ANS:	B	PTS:	1	DIF:	Easy	REF:	10.4
KEY:	Chemistry | general chemistry | materials chemistry | metal		
MSC:	Conceptual

	53.	The net number of spheres in the face-centered cubic unit cell is 4.

ANS:	T	PTS:	1	DIF:	Easy	REF:	10.4
KEY:	Chemistry | general chemistry | phases | solid | crystalline solids | cubic unit cell
MSC:	Conceptual

	54.	Steel is a substitutional alloy.

ANS:	F	PTS:	1	DIF:	Easy	REF:	10.4
KEY:	Chemistry | general chemistry | materials chemistry | metal		
MSC:	Conceptual

	55.	Which of the following statements is true about p-type silicon?
A)	It is produced by doping Si with P or As.	
B)	Protons are the mobile charge carriers.	
C)	It does not conduct electricity as well as pure Si.	
D)	All are true.	
E)	None is true.	

ANS:	E	PTS:	1	DIF:	Easy	REF:	10.5
KEY:	Chemistry | general chemistry | materials chemistry | metal | semiconductor
MSC:	Conceptual

	56.	Doping Se with B would produce a(n) __________ semiconductor with __________ conductivity compared to pure Se.
A)	p-type, increased	
B)	n-type, decreased	
C)	n-type, increased	
D)	p-type, decreased	
E)	intrinsic, identical	

ANS:	A	PTS:	1	DIF:	Easy	REF:	10.5
KEY:	Chemistry | general chemistry | materials chemistry | metal | semiconductor
MSC:	Conceptual

	57.	A material is made from Al, Ga, and As. The mole fraction of each element is 0.25, 0.26, and 0.49, respectively. This material would be
A)	a metallic conductor because Al is present	
B)	an insulator	
C)	a p-type semiconductor	
D)	an n-type semiconductor	
E)	none of the above	

ANS:	C	PTS:	1	DIF:	Moderate	REF:	10.5
KEY:	Chemistry | general chemistry | materials chemistry | metal | semiconductor
MSC:	Conceptual

	58.	Which of the compounds below is an example of a network solid?
A)	S8(s)	
B)	SiO2(s)	
C)	MgO(s)	
D)	NaCl(s)	
E)	C25H52(s)	

ANS:	B	PTS:	1	DIF:	Easy	REF:	10.5
KEY:	Chemistry | general chemistry | phases | solid | structures of crystalline solids | covalent network solid		MSC:	Conceptual

	59.	Which of the compounds below is not an example of a molecular solid?
A)	I2(s)	
B)	SiO2(s)	
C)	CO2(s)	
D)	H2O(s)	
E)	C25H52(s)	

ANS:	B	PTS:	1	DIF:	Easy	REF:	10.6
KEY:	Chemistry | general chemistry | phases | solid | structures of crystalline solids | molecular solid	MSC:	Conceptual

	60.	Ice is a molecular solid.

ANS:	T	PTS:	1	DIF:	Easy	REF:	10.6
KEY:	Chemistry | general chemistry | phases | solid | classification of solids | molecular solid	MSC:	Conceptual

	61.	Which of these statements is incorrect?
A)	Molecular solids have high melting points.	
B)	The binding forces in a molecular solid include London dispersion forces.	
C)	Ionic solids have high melting points.	
D)	Ionic solids are insulators.	
E)	All of the statements (A-D) are correct.	

ANS:	A	PTS:	1	DIF:	Easy	REF:	10.7
KEY:	Chemistry | general chemistry | phases | solid | classification of solids
MSC:	Conceptual

	62.	At room temperature, CsF is expected to be
A)	a gas	
B)	a conducting solid	
C)	a liquid	
D)	a brittle solid	
E)	a soft solid	

ANS:	D	PTS:	1	DIF:	Easy	REF:	10.7
KEY:	Chemistry | general chemistry | phases | solid | properties of solids	
MSC:	Conceptual

	63.	A solid crystal of NaCl is
A)	soft, low melting, a good electrical conductor	
B)	hard, high melting, a good electrical conductor	
C)	soft, low melting, a poor electrical conductor	
D)	hard, high melting, a poor electrical conductor	
E)	soft, high melting, a poor electrical conductor	

ANS:	D	PTS:	1	DIF:	Easy	REF:	10.7
KEY:	Chemistry | general chemistry | phases | solid | properties of solids	
MSC:	Conceptual

	64.	Solid MgO has the same crystal structure as NaCl. How many oxide ions surround each Mg2+ ion as nearest neighbors in MgO?
A)	4	
B)	6	
C)	8	
D)	12	
E)	none of these	

ANS:	B	PTS:	1	DIF:	Moderate	REF:	10.7
KEY:	Chemistry | general chemistry | phases | solid | structures of crystalline solids | ionic solid	MSC:	Conceptual

	65.	Which of the following has the highest melting temperature?
A)	H2O	
B)	CO2	
C)	S8	
D)	MgF2	
E)	P4	

ANS:	D	PTS:	1	DIF:	Easy	REF:	10.7
KEY:	Chemistry | general chemistry | phases | solid | properties of solids | melting point
MSC:	Conceptual

	66.	A certain solid substance that is very hard, has a high melting point, and is nonconducting unless melted is most likely to be:
A)	I2	
B)	NaCl	
C)	CO2	
D)	H2O	
E)	Cu	

ANS:	B	PTS:	1	DIF:	Easy	REF:	10.7
KEY:	Chemistry | general chemistry | phases | solid | classification of solids
MSC:	Conceptual

	67.	Which of these statements is false?
A)	Diamond is a covalent crystal.	
B)	The size of the unit cell of Li and Cs is the same.	
C)	Molecular crystals usually have low melting points.	
D)	Metallic crystals are usually good electrical conductors.	
E)	None of the statements is false.	

ANS:	B	PTS:	1	DIF:	Easy	REF:	10.7
KEY:	Chemistry | general chemistry | phases | solid	MSC:	Conceptual

	68.	An ionic crystalline solid, MX2, has a cubic unit cell. Which of the following arrangements of the ions is consistent with the stoichiometry of the compound?
A)	M2+ ions at the corners and at each face, 8 X– ions at the tetrahedral centers	
B)	M2+ ions at each face, X– ions at the corners	
C)	M2+ ions at the corners, X– ions at the faces, and 2 X– ions at the tetrahedralcenters	
D)	4 M2+ ions at the body centers, X– ions at the corners and at the faces	
E)	M2+ ions at the corners and at the faces, 4 X– ions at the octahedral centers	

ANS:	A	PTS:	1	DIF:	Easy	REF:	10.7
KEY:	Chemistry | general chemistry | phases | solid | structures of crystalline solids | ionic solid	MSC:	Conceptual

	69.	Lithium chloride crystallizes in a face-centered cubic structure. The unit cell length is 5.14 ´ 10–8 cm. The chloride ions are touching each other along the face diagonal of the unit cell. The lithium ions fit into the holes between the chloride ions. What is the mass of LiCl in a unit cell?
A)	7.04 ´ 10–23 g	
B)	1.41 ´ 10–22 g	
C)	2.82 ´ 10–22 g	
D)	4.22 ´ 10–22 g	
E)	5.63 ´ 10–22 g	

ANS:	C	PTS:	1	DIF:	Difficult	REF:	10.7
KEY:	Chemistry | general chemistry | phases | solid | structures of crystalline solids | ionic solid	MSC:	Quantitative

	70.	How would you expect the melting point of CCl4 to compare to that of NaCl?
A)	It should be lower because NaCl forms an extended ionic crystal lattice, whereas CCl4 is a covalently-bonded small molecule.	
B)	It should be similar since they are both ionic solids.	
C)	It should be higher because the bonds are stronger due to the higher charge on C (+4).	
D)	It should be higher because CCl4 is larger than NaCl.	
E)	It is not possible to say anything about their melting points without more information.	

ANS:	A	PTS:	1	DIF:	Easy	REF:	10.7
KEY:	Chemistry | general chemistry | phases | solid | properties of solids | melting point
MSC:	Conceptual

	71.	In the unit cell of sphalerite, Zn2+ ions occupy half the tetrahedral holes in a face-centered cubic lattice of S2– ions. The number of formula units of ZnS in the unit cell is:
A)	6	
B)	4	
C)	3	
D)	2	
E)	1	

ANS:	B	PTS:	1	DIF:	Difficult	REF:	10.7
KEY:	Chemistry | general chemistry | phases | solid | structures of crystalline solids
MSC:	Conceptual

	72.	The unit cell in a certain lattice consists of a cube formed by an anion at each corner, an anion in the center, and a cation at the center of each face. The unit cell contains a net:
A)	5 anions and 6 cations	
B)	5 anions and 3 cations	
C)	2 anions and 3 cations	
D)	3 anions and 4 cations	
E)	2 anions and 2 cations	

ANS:	C	PTS:	1	DIF:	Moderate	REF:	10.7
KEY:	Chemistry | general chemistry | phases | solid | crystalline solids | cubic unit cell
MSC:	Conceptual

	73.	Which of the following statements about the closest packing of spheres in binary ionic solids is false?
A)	The packing is done in a way that minimizes repulsions among ions with like charges.	
B)	The packing arrangement maximizes electrostatic attractions among oppositely charged ions.	
C)	For spheres of a given diameter, tetrahedral holes are larger than octahedral holes.	
D)	Trigonal holes are so small that they are never occupied.	
E)	None of these.	

ANS:	C	PTS:	1	DIF:	Moderate	REF:	10.7
KEY:	Chemistry | general chemistry | phases | solid | structures of crystalline solids
MSC:	Conceptual

	74.	An atom in an octahedral hole is surrounded by ____ atoms.
A)	2	
B)	3	
C)	4	
D)	6	
E)	8	

ANS:	D	PTS:	1	DIF:	Moderate	REF:	10.7
KEY:	Chemistry | general chemistry | phases | solid | structures of crystalline solids
MSC:	Conceptual

	75.	A salt, MY, crystallizes in a body-centered cubic structure with a Y– anion at each cube corner and an M+ cation at the cube center. Assuming that the Y– anions touch each other and the M+ cation at the center, and the radius of Y– is 1.50 ´ 102 pm, the radius of M+ is:
A)	62.0 pm	
B)	110. pm	
C)	124 pm	
D)	220. pm	
E)	none of these	

ANS:	B	PTS:	1	DIF:	Difficult	REF:	10.7
KEY:	Chemistry | general chemistry | phases | solid | calculations with unit cell dimensions
MSC:	Quantitative

	76.	Sodium oxide (Na2O) crystallizes in a structure in which the O2– ions are in a face-centered cubic lattice and the Na+ ions are in tetrahedral holes. The number of Na+ ions in the unit cell is:
A)	2	
B)	4	
C)	6	
D)	8	
E)	none of these	

ANS:	D	PTS:	1	DIF:	Moderate	REF:	10.7
KEY:	Chemistry | general chemistry | phases | solid | structures of crystalline solids | ionic solid	MSC:	Conceptual

	77.	A certain metal fluoride crystallizes in such a way that the fluoride ions occupy simple cubic lattice sites, while the metal atoms occupy the body centers of half the cubes. The formula for the metal fluoride is:
A)	MF2	
B)	M2F	
C)	MF	
D)	MF8	
E)	none of these	

ANS:	A	PTS:	1	DIF:	Moderate	REF:	10.7
KEY:	Chemistry | general chemistry | phases | solid | structures of crystalline solids | ionic solid	MSC:	Conceptual

	78.	Which of the following is most likely to be a solid at room temperature?
A)	Na2S	
B)	HF	
C)	NH3	
D)	N2	
E)	H2O	

ANS:	A	PTS:	1	DIF:	Easy	REF:	10.7
KEY:	Chemistry | general chemistry | phases | solid | classification of solids
MSC:	Conceptual

	79.	On the basis of your knowledge of bonding in liquids and solids, which of the following has the lowest melting temperature?
A)	NaCl	
B)	Na	
C)	Cl2	
D)	SiO2	
E)	More information is needed.	

ANS:	C	PTS:	1	DIF:	Moderate	REF:	10.7
KEY:	Chemistry | general chemistry | phases | solid | classification of solids
MSC:	Conceptual

	80.	Which of the following substances would you expect to have the lowest boiling point?
A)	diamond	
B)	methane, CH4	
C)	sodium nitrate, NaNO3	
D)	glycerine, C3H5(OH)3	
E)	copper	

ANS:	B	PTS:	1	DIF:	Moderate	REF:	10.7
KEY:	Chemistry | general chemistry | phases | solid | classification of solids
MSC:	Conceptual

	81.	On a relative basis, the weaker the intermolecular forces in a substance,
A)	the greater its heat of vaporization	
B)	the more it deviates from ideal gas behavior	
C)	the greater its vapor pressure at a particular temperature	
D)	the higher its melting point	
E)	none of these	

ANS:	C	PTS:	1	DIF:	Easy	REF:	10.8
KEY:	Chemistry | general chemistry | phases | liquid | intermolecular forces
MSC:	Conceptual

	82.	At normal atmospheric pressure and a temperature of 0°C, which phase(s) of H2O can exist?
A)	ice and water	
B)	ice and water vapor	
C)	water only	
D)	water vapor only	
E)	ice only	

ANS:	A	PTS:	1	DIF:	Easy	REF:	10.8
KEY:	Chemistry | general chemistry | phases | phase transitions | melting point
MSC:	Conceptual

	83.	The process of condensation happens when which of the following occurs?
A)	A solid becomes a liquid.	
B)	A liquid becomes a solid.	
C)	A gas becomes a liquid.	
D)	A liquid becomes a gas.	
E)	A gas becomes a solid.	

ANS:	C	PTS:	1	DIF:	Easy	REF:	10.8
KEY:	Chemistry | general chemistry | phases | phase transitions	MSC:	Conceptual

	84.	Which of the following processes must exist in equilibrium with the evaporation process when a measurement of vapor pressure is made?
A)	fusion	
B)	vaporization	
C)	sublimation	
D)	boiling	
E)	condensation	

ANS:	E	PTS:	1	DIF:	Easy	REF:	10.8
KEY:	Chemistry | general chemistry | phases | phase transitions | vapor pressure
MSC:	Conceptual

	85.	Assume 12,500 J of energy is added to 2.0 moles (36 grams) of H2O as an ice sample at 0°C. The molar heat of fusion is 6.02 kJ/mol. The specific heat of liquid water is 4.18 J/g °C. The molar heat of vaporization is 40.6 kJ/mol. The resulting sample contains which of the following?
A)	only ice	
B)	ice and water	
C)	only water	
D)	water and water vapor	
E)	only water vapor	

ANS:	C	PTS:	1	DIF:	Moderate	REF:	10.8
KEY:	Chemistry | general chemistry | phases | phase transitions | Clausius-Clapeyron equation	MSC:	Quantitative

	86.	You are given the following boiling point data. Which one of the liquids would you expect to have the highest vapor pressure at room temperature?
A)	water, H2O                                              100°C	
B)	methanol, CH3OH                                 64.96°C	
C)	ethanol, CH3CH2OH                               78.5°C	
D)	diethyl ether, CH3OH2–O–CH2CH3          34.5°C	
E)	ethylene glycol, HO–CH2–CH2–OH         198°C	

ANS:	D	PTS:	1	DIF:	Easy	REF:	10.8
KEY:	Chemistry | general chemistry | phases | phase transitions | vapor pressure
MSC:	Conceptual

	87.	Given below are the temperatures at which two different liquid compounds with the same empirical formula have a vapor pressure of 400 torr.
			Compound	T (°C)	
			dimethyl ether, CH3–O–CH3	–37.8	
			ethanol, CH3CH2OH	63.5	
		Which of the following statements (a–d) is false?	

A)	Increasing the temperature will increase the vapor pressure of both liquids.	
B)	Intermolecular attractive forces are stronger in (liquid) ethanol than in (liquid) dimethyl ether.	
C)	The normal boiling point of dimethyl ether will be higher than the normal boiling point of ethanol.	
D)	The reason that the temperature at which the vapor pressure is 400 torr is higher for ethanol (than for dimethyl ether) is that there is strong hydrogen bonding in ethanol.	
E)	None of these is false.	

ANS:	C	PTS:	1	DIF:	Easy	REF:	10.8
KEY:	Chemistry | general chemistry | phases | phase transitions | vapor pressure
MSC:	Conceptual

	88.	Given the graph below, what is the boiling point of chloroform at standard pressure?

A)	77°C	
B)	34°C	
C)	98°C	
D)	60°C	
E)	The graph does not give that information.	

ANS:	D	PTS:	1	DIF:	Easy	REF:	10.8
KEY:	Chemistry | general chemistry | phases | phase transitions | vapor pressure
MSC:	Conceptual

	89.	A liquid placed in a closed container will evaporate until equilibrium is reached. At equilibrium, which of the statements (A-D) is false?
A)	The partial pressure exerted by the vapor molecules is called the vapor pressure of the liquid.	
B)	Liquid molecules are still evaporating.	
C)	The number of vapor molecules remains essentially constant.	
D)	The boundary (meniscus) between liquid and vapor disappears.	
E)	All of these are true.	

ANS:	D	PTS:	1	DIF:	Easy	REF:	10.8
KEY:	Chemistry | general chemistry | phases | phase transitions | vapor pressure
MSC:	Conceptual

	90.	Which one of the following decreases as the strength of the attractive intermolecular forces increases?
A)	the heat of vaporization	
B)	the normal boiling temperature	
C)	the extent of deviations from the ideal gas law	
D)	the sublimation temperature of a solid	
E)	the vapor pressure of a liquid	

ANS:	E	PTS:	1	DIF:	Easy	REF:	10.8
KEY:	Chemistry | general chemistry | phases | liquid | intermolecular forces
MSC:	Conceptual

	91.	Knowing that DHvap for water is 40.7 kJ/mol, calculate Pvap of water at 58°C.
A)	5.3 torr	
B)	456 torr	
C)	14.8 torr	
D)	759 torr	
E)	144 torr	

ANS:	E	PTS:	1	DIF:	Moderate	REF:	10.8
KEY:	Chemistry | general chemistry | phases | phase transitions | Clausius-Clapeyron equation	MSC:	Quantitative

	92.	Water sits in an open beaker. Assuming constant temperature and pressure, the rate of evaporation decreases as the water evaporates.

ANS:	F	PTS:	1	DIF:	Easy	REF:	10.8
KEY:	Chemistry | general chemistry | phases | phase transitions	MSC:	Conceptual

	93.	Water sits in an open beaker. Assuming constant temperature and pressure, the vapor pressure of the water decreases as the water evaporates.

ANS:	F	PTS:	1	DIF:	Easy	REF:	10.8
KEY:	Chemistry | general chemistry | phases | phase transitions | vapor pressure
MSC:	Conceptual

	94.	Generally the vapor pressure of a liquid is related to:
I.	the amount of liquid	
II.	atmospheric pressure	
III.	temperature	
IV.	intermolecular forces	

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

ANS:	D	PTS:	1	DIF:	Easy	REF:	10.8
KEY:	Chemistry | general chemistry | phases | phase transitions | vapor pressure
MSC:	Conceptual

	95.	In which of the following processes will energy be evolved as heat?
A)	sublimation	
B)	crystallization	
C)	vaporization	
D)	melting	
E)	none of these	

ANS:	B	PTS:	1	DIF:	Easy	REF:	10.8
KEY:	Chemistry | general chemistry | phases | phase transitions	MSC:	Conceptual

	96.	When one mole of benzene is vaporized at a constant pressure of 1.00 atm and at its boiling point of 353.0 K, 30.56 kJ of energy (heat) is absorbed and the volume change is +28.90 L. What is DE for this process? (1 L·atm = 101.3 J)
A)	30.56 kJ	
B)	59.46 kJ	
C)	33.49 kJ	
D)	1.66 kJ	
E)	27.63 kJ	

ANS:	E	PTS:	1	DIF:	Moderate	REF:	10.8
KEY:	Chemistry | general chemistry | phases | phase transitions | Clausius-Clapeyron equation	MSC:	Quantitative

	97.	When one mole of benzene is vaporized at a constant pressure of 1.00 atm and at its boiling point of 353.0 K, 30.53 kJ of energy (heat) is absorbed and the volume change is +28.90 L. What is DH for this process? (1 L·atm = 101.3 J)
A)	27.60 kJ	
B)	33.46 kJ	
C)	1.63 kJ	
D)	30.53 kJ	
E)	59.43 kJ	

ANS:	D	PTS:	1	DIF:	Moderate	REF:	10.8
KEY:	Chemistry | general chemistry | phases | phase transitions | Clausius-Clapeyron equation	MSC:	Quantitative

	98.	The normal boiling point of liquid X is less than that of Y, which is less than that of Z. Which of the following is the correct order of increasing vapor pressure of the three liquids at STP?
A)	X, Y, Z	
B)	Z, Y, X	
C)	Y, X, Z	
D)	X, Z, Y	
E)	Y, Z, X	

ANS:	B	PTS:	1	DIF:	Easy	REF:	10.8
KEY:	Chemistry | general chemistry | phases | phase transitions | vapor pressure
MSC:	Conceptual

	99.	The vapor pressure of water at 100.0°C is
A)	85 torr	
B)	760 torr	
C)	175 torr	
D)	1 torr	
E)	More information is needed.	

ANS:	B	PTS:	1	DIF:	Easy	REF:	10.8
KEY:	Chemistry | general chemistry | phase | phase transitions | vapor pressure
MSC:	Conceptual

	100.	How much energy is needed to convert 54.1 grams of ice at 0.00°C to water at 75.0°C?
     specific heat (ice) = 2.10 J/g°C
     specific heat (water) = 4.18 J/g°C
     heat of fusion = 333 J/g
     heat of vaporization = 2258 J/g
A)	17.0 kJ	
B)	1.94 kJ	
C)	26.5 kJ	
D)	35.0 kJ	
E)	139 kJ	

ANS:	D	PTS:	1	DIF:	Moderate	REF:	10.8
KEY:	Chemistry | general chemistry | phases | phase transitions | phase transition enthalpy change	MSC:	Quantitative

	101.	The vapor pressure of water at 80°C is
A)	0.48 atm	
B)	1.00 atm	
C)	1.20 atm	
D)	2.00 atm	
E)	5.00 atm	

ANS:	A	PTS:	1	DIF:	Easy	REF:	10.8
KEY:	Chemistry | general chemistry | phases | phase transitions | vapor pressure
MSC:	Conceptual

	102.	Which of the following has the highest boiling point?
A)	chalk (calcium carbonate)	
B)	ice (water)	
C)	window cleaner (ammonia)	
D)	motor oil (hydrocarbon chains)	
E)	helium gas inside a party balloon	

ANS:	A	PTS:	1	DIF:	Easy	REF:	10.8
KEY:	Chemistry | general chemistry | phases | phase transitions | vapor pressure
MSC:	Conceptual

	103.	How many grams of ice would be melted by the energy obtained as 16.2 g of steam is condensed at 100°C and cooled to 0°C? 
     specific heat (ice) = 2.10 J/g°C
     specific heat (water) = 4.18 J/g°C
     heat of fusion = 333 J/g
     heat of vaporization = 2258 J/g
A)	43.4 kg	
B)	36.6 kg	
C)	130 g	
D)	6.77 kg	
E)	20 g	

ANS:	C	PTS:	1	DIF:	Moderate	REF:	10.8
KEY:	Chemistry | general chemistry | phases | phase transitions | phase transition enthalpy change	MSC:	Quantitative

	104.	The heat of combustion of bituminous coal is 2.50 ´ 104 J/g. What quantity of the coal is required to produce the energy to convert 106.9 pounds of ice at 0.00°C to steam at 100.°C?
     specific heat (ice) = 2.10 J/g°C
     specific heat (water) = 4.18 J/g°C
     heat of fusion = 333 J/g
     heat of vaporization = 2258 J/g
A)	5.84 kg	
B)	0.646 kg	
C)	0.811 kg	
D)	4.38 kg	
E)	1.46 kg	

ANS:	A	PTS:	1	DIF:	Moderate	REF:	10.8
KEY:	Chemistry | general chemistry | phases | phase transitions | phase transition enthalpy change	MSC:	Quantitative

	105.	The process of changing from a vapor to a liquid is vaporization.

ANS:	F	PTS:	1	DIF:	Easy	REF:	10.8
KEY:	Chemistry | general chemistry | phases | phase transitions	MSC:	Conceptual

	106.	A certain substance, X, has a triple-point temperature of 20°C at a pressure of 2.0 atm. Which one of the statements (A-D) cannot possibly be true?
A)	X can exist as a liquid above 20°C.	
B)	X can exist as a solid above 20°C.	
C)	Liquid X can exist as a stable phase at 25°C, 1 atm.	
D)	Both liquid and solid X have the same vapor pressure at 20°C.	
E)	All of the statements (A-D) could be true.	

ANS:	C	PTS:	1	DIF:	Moderate	REF:	10.9
KEY:	Chemistry | general chemistry | phases | phase transitions | phase diagram | triple point	MSC:	Conceptual

	107.	Which statement regarding water is true?
A)	Energy must be given off in order to break down the crystal lattice of ice to a liquid.	
B)	Hydrogen bonds are stronger than covalent bonds.	
C)	Liquid water is less dense than solid water.	
D)	Only covalent bonds are broken when ice melts.	
E)	All of the statements (A–D) are false.	

ANS:	E	PTS:	1	DIF:	Easy	REF:	10.9
KEY:	Chemistry | general chemistry | phases | phase transitions	MSC:	Conceptual

	108.	The triple point of iodine is at 90 torr and 115°C. This means that liquid I2
A)	is more dense than I2(s)	
B)	cannot exist above 115°C	
C)	cannot exist at 1 atmosphere pressure	
D)	cannot have a vapor pressure less than 90 torr	
E)	can exist at pressure of 10 torr	

ANS:	D	PTS:	1	DIF:	Easy	REF:	10.9
KEY:	Chemistry | general chemistry | phases | phase transitions | phase diagram | triple point	MSC:	Conceptual

	109.	The triple point of CO2 is at 5.2 atm and –57°C. Under atmospheric conditions present in a typical Boulder, Colorado, laboratory (P = 630 torr, T = 23°C), solid CO2 will:
A)	remain solid	
B)	boil	
C)	melt	
D)	sublime	
E)	none of these	

ANS:	D	PTS:	1	DIF:	Moderate	REF:	10.9
KEY:	Chemistry | general chemistry | phases | phase transitions | phase diagram | triple point	MSC:	Conceptual

	110.	Choose the correct statement about the diagram below.

A)	The diagram is qualitatively correct for water.	
B)	The diagram shows that the melting point of the solid increases with increasing pressure.	
C)	The diagram shows the triple point above 1 atm pressure.	
D)	The diagram could represent the phase diagram of CO2.	
E)	None of the above statements is correct.	

ANS:	B	PTS:	1	DIF:	Easy	REF:	10.9
KEY:	Chemistry | general chemistry | phases | phase transitions | phase diagram
MSC:	Conceptual

	111.	Below is a phase diagram for compound Q. You wish to purify a sample of Q that was collected at P = 1.0 atm and T = 100 K by subliming it. In order to sublime the sample, you should:

A)	Increase P to 1.5 atm and then increase T to 300 K.	
B)	Increase T to 300 K, keeping P = 1.0 atm.	
C)	Lower P to 0.5 atm and then increase T to 200 K.	
D)	Increase T to 300 K and then lower P to 0.5 atm.	
E)	Abandon the attempt to sublime Q.	

ANS:	C	PTS:	1	DIF:	Easy	REF:	10.9
KEY:	Chemistry | general chemistry | phases | phase transitions | phase diagram
MSC:	Conceptual

	112.	Shown below is a phase diagram for compound Y. At 25°C and 1 atm Y will exist as a:

A)	solid	
B)	liquid	
C)	gas	
D)	gas/liquid at equilibrium	
E)	gas/solid at equilibrium	

ANS:	B	PTS:	1	DIF:	Easy	REF:	10.9
KEY:	Chemistry | general chemistry | phases | phase transitions | phase diagram
MSC:	Conceptual

	113.	Below is a phase diagram for compound Y. The normal boiling point of Y is most likely:

A)	21°C	
B)	47°C	
C)	63°C	
D)	18°C	
E)	0°C	

ANS:	B	PTS:	1	DIF:	Easy	REF:	10.9
KEY:	Chemistry | general chemistry | phases | phase transitions | phase diagram
MSC:	Conceptual

	114.	Shown below is a phase diagram for compound Y.

How will the melting point of Y change with increased pressure?
A)	increase	
B)	decrease	
C)	remain the same	
D)	not enough information given	
E)	increase and then decrease	

ANS:	A	PTS:	1	DIF:	Easy	REF:	10.9
KEY:	Chemistry | general chemistry | phases | phase transitions | phase diagram
MSC:	Conceptual

	115.	Based on the phase diagram shown below, which of the following statements are correct?

 I.	Sublimation occurs at a point in the transformation that occurs along a straight line from point A to point F.	
II.	C and E represent points where the gas and liquid phases are in equilibrium.	
III.	DHvap can be measured at point B.	
IV.	Molecules at point D have a greater average kinetic energy than those at point F.	
V.	The temperature at point E is called the critical temperature of the compound.	

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

ANS:	E	PTS:	1	DIF:	Moderate	REF:	10.9
KEY:	Chemistry | general chemistry | phases | phase transitions | phase diagram
MSC:	Conceptual

	116.	A certain substance has the phase diagram shown below. At which of the following values of T and P is the substance a pure liquid?

A)	T = 8°C, P = 1 atm	
B)	T = 10°C, P = 0.5 atm	
C)	T = 70°C, P = 1.2 atm	
D)	T = 80°C, P = 1 atm	
E)	T = 10°C, P = 1 atm	

ANS:	C	PTS:	1	DIF:	Easy	REF:	10.9
KEY:	Chemistry | general chemistry | phases | phase transitions | phase diagram
MSC:	Conceptual

	117.	A sample consisting of CO2(g) and CO2(s) at equilibrium at –78°C and 1 atm pressure is heated to –30°C and the pressure is increased to 8 atm. Based on the phase diagram below, what will happen?

A)	At equilibrium, only CO2(g) will be present.	
B)	All of the CO2 will be converted to CO2(l).	
C)	At equilibrium, CO2(g) and CO2(l) will be present.	
D)	The melting point of the CO2(s) will decrease.	
E)	None of these.	

ANS:	B	PTS:	1	DIF:	Easy	REF:	10.9
KEY:	Chemistry | general chemistry | phases | phase transitions | phase diagram
MSC:	Conceptual

	118.	Given the phase diagram below, which of the following statements (A–D) is false?

A)	The solid has a higher density than the liquid.	
B)	At some (constant) temperature, the gaseous substance can be compressed into a solid and then into a liquid in this order.	
C)	When phase A is compressed at constant temperature at point X, no change is observed.	
D)	When heated at 1 atm, this substance will first melt, then boil.	
E)	None of the above statements is false.	

ANS:	A	PTS:	1	DIF:	Easy	REF:	10.9
KEY:	Chemistry | general chemistry | phases | phase transitions | phase diagram
MSC:	Conceptual

	119.	The density of the solid phase of a substance is 0.90 g/cm3 and the density of the liquid phase is 1.0 g/cm3. A large increase in pressure will
A)	lower the freezing point	
B)	raise the freezing point	
C)	lower the boiling point	
D)	raise the triple point	
E)	lower the triple point	

ANS:	A	PTS:	1	DIF:	Moderate	REF:	10.9
KEY:	Chemistry | general chemistry | phases | phase transitions | phase diagram
MSC:	Conceptual

	120.	Make a sketch to show the hydrogen bonding between two acetic acid molecules (HC2H3O2).

ANS:	

See Sec. 10.1 of Zumdahl, Chemistry

PTS:	1	DIF:	Easy	REF:	10.1	
KEY:	Chemistry | general chemistry | phases | liquid | intermolecular forces | hydrogen bonding	MSC:	Conceptual

	121.	If you have 10.0 moles of BH3 and 5.0 moles of HF, which amount exhibits the most hydrogen bonding? Explain.
Check question

ANS:	
HF; Hydrogen bonding only occurs between molecules where hydrogen is bonded to nitrogen, oxygen, or fluorine. Even though more BH3 is present, it does not exhibit any hydrogen bonding at all.

See Sec. 10.1 of Zumdahl, Chemistry.

PTS:	1	DIF:	Easy	REF:	10.1	
KEY:	Chemistry | general chemistry | phases | liquid | intermolecular forces
MSC:	Conceptual

	122.	The particularly strong dipole-dipole interaction between hydrogen in one molecule and nitrogen in another molecule is known as a __________.

ANS:	
hydrogen bond

PTS:	1	DIF:	Easy	REF:	10.1	
KEY:	Chemistry | general chemistry | phases | liquid | intermolecular forces | hydrogen bonding	MSC:	Conceptual

	123.	The relatively weak forces that exist among noble gas atoms are __________.

ANS:	
London dispersion forces

PTS:	1	DIF:	Easy	REF:	10.1	
KEY:	Chemistry | general chemistry | phases | liquid | intermolecular forces | London forces
MSC:	Conceptual

	124.	The meniscus of mercury curves downward at the edges. Explain using the concepts of cohesion and adhesion.

ANS:	
In mercury the cohesive forces within the liquid are stronger than the adhesive forces toward glass.

See Sec. 10.2 of Zumdahl, Chemistry.

PTS:	1	DIF:	Moderate	REF:	10.2	
KEY:	Chemistry | general chemistry | phases | liquid | properties of liquids
MSC:	Conceptual

	125.	The resistance of a liquid to an increase in its surface area is the __________ of the liquid.

ANS:	
surface tension

PTS:	1	DIF:	Easy	REF:	10.2	
KEY:	Chemistry | general chemistry | phases | liquid | properties of liquids | surface tension
MSC:	Conceptual

	126.	The structures of crystalline solids are most commonly determined by __________.

ANS:	
x-ray diffraction

PTS:	1	DIF:	Easy	REF:	10.3	
KEY:	Chemistry | general chemistry | phases | solid | x-ray diffraction	
MSC:	Conceptual

	127.	In a(n) __________ alloy some of the host metal atoms are replaced by other metal atoms of similar size.

ANS:	
substitutional

PTS:	1	DIF:	Easy	REF:	10.4	
KEY:	Chemistry | general chemistry | materials chemistry | metal		
MSC:	Conceptual

	128.	Iodine moves directly from solid to gas in a process called __________.

ANS:	
sublimation

PTS:	1	DIF:	Easy	REF:	10.8	
KEY:	Chemistry | general chemistry | phases | phase transitions	MSC:	Conceptual

	129.	Explain why water boils at a lower temperature up in the mountains versus at sea level. Include at least one microscopic drawing in your explanation.

ANS:	
The boiling point of a liquid is the temperature at which the vapor pressure of the liquid is exactly the same as the pressure of the atmosphere around it. Water boils at a lower temperature up in the mountains because at high altitudes the atmospheric pressure is lower (see pictures A and B). Boiling occurs when the water is hot enough to have the same vapor pressure as the surrounding air pressure, so that it can form bubbles. Since the air pressure is lower at high altitudes, the water does not have to get as hot for boiling to occur. It will take more heat for water at sea level to attain the same pressure as the surrounding air since the atmospheric pressure is higher (see picture B).
                     Picture A                       Picture B
               (high altitudes)                   (low altitudes)

See Sec. 10.8 of Zumdahl, Chemistry.

PTS:	1	DIF:	Moderate	REF:	10.8	
KEY:	Chemistry | general chemistry | phases | phase transitions | vapor pressure
MSC:	Conceptual

	130.	100. g of ice at 0°C is added to 300.0 g of water at 60°C. Assuming no transfer of heat to the surroundings, what is the temperature of the liquid water after all the ice has melted and equilibrium is reached?
     specific heat (ice) = 2.10 J/g°C
     specific heat (water) = 4.18 J/g°C
     heat of fusion = 333 J/g
     heat of vaporization = 2258 J/g

ANS:	
25.0°C

100.g (333 J/g) + 100.g(Tf–0°C)(4.18 J/g°C) = –300.0g(Tf–60°C)(4.18 J/g°C)
33300 + 418Tf = –1254Tf + 75240    (using underline to track sig figs)
1672Tf = 41940;   Tf = 25°C

PTS:	1	DIF:	Moderate	REF:	10.8	
KEY:	Chemistry | general chemistry | phases | phase transitions | phase transition enthalpy change	MSC:	Quantitative

	131.	For each of the following pairs of substances, select the one expected to have the higher melting point:
I.	H2O, H2S		II.	HCl, NaCl		III.	CH4, C3H8
A)	H2O, HCl, C3H8	
B)	H2O, NaCl, C3H8	
C)	H2O, NaCl, CH4	
D)	H2S, HCl, CH4	
E)	H2S, NaCl, CH4	

ANS:	B	PTS:	1	DIF:	Moderate	REF:	10.1
KEY:	Chemistry | general chemistry | phases | intermolecular forces	
MSC:	Conceptual

	132.	For each of the following pairs of substances, select the one expected to have the lower melting point:
I.	H2O, H2S		II.	HCl, NaCl		III.	CH4, C3H8
A)	H2O, HCl, C3H8	
B)	H2O, NaCl, C3H8	
C)	H2O, HCl, CH4	
D)	H2S, HCl, CH4	
E)	H2S, NaCl, CH4	

ANS:	D	PTS:	1	DIF:	Moderate	REF:	10.1
KEY:	Chemistry | general chemistry | phases | intermolecular forces	
MSC:	Conceptual

	133.	Which of the following compounds is expected to have the HIGHEST boiling point?
A)	CH3OCH3	
B)	CH3CH2OH	
C)	CH3CH2CH2CH3	
D)	CH3CH2CH3	
E)	CH3Cl	

ANS:	B	PTS:	1	DIF:	Moderate	REF:	10.1
KEY:	Chemistry | general chemistry | phases | intermolecular forces | hydrogen bonds
MSC:	Conceptual

	134.	Which of the following compounds is expected to have the HIGHEST melting point?
A)	CH3OCH3	
B)	CH3CH2OH	
C)	CH3CH2CH2CH3	
D)	CH3CH2CH3	
E)	CH3Cl	

ANS:	B	PTS:	1	DIF:	Moderate	REF:	10.1
KEY:	Chemistry | general chemistry | phases | intermolecular forces | hydrogen bonds
MSC:	Conceptual

	135.	Which of the following compounds is expected to have the LOWEST melting point?
A)	CH3OCH3	
B)	CH3CH2OH	
C)	CH3CH2CH2CH3	
D)	CH3CH2CH3	
E)	CH3Cl	

ANS:	D	PTS:	1	DIF:	Moderate	REF:	10.1
KEY:	Chemistry | general chemistry | phases | intermolecular forces	
MSC:	Conceptual

	136.	Which of the following compounds is expected to have the LOWEST boiling point?
A)	CH3OCH3	
B)	CH3CH2OH	
C)	CH3CH2CH2CH3	
D)	CH3CH2CH3	
E)	CH3Cl	

ANS:	D	PTS:	1	DIF:	Moderate	REF:	10.1
KEY:	Chemistry | general chemistry | phases | intermolecular forces	
MSC:	Conceptual

	137.	The measure of resistance to flow of a liquid is
A)	van der Waals forces	
B)	vapor pressure	
C)	London forces	
D)	surface tension	
E)	viscosity	

ANS:	E	PTS:	1	DIF:	Easy	REF:	10.2
KEY:	Chemistry | general chemistry | phases | liquid | properties of liquids
MSC:	Conceptual

	138.	Which of the following would be expected to have the lowest heat of vaporization?
A)	H2O	
B)	NH3	
C)	PH3	
D)	AsH3	
E)	CH4	

ANS:	E	PTS:	1	DIF:	Easy	REF:	10.8
KEY:	Chemistry | general chemistry | phases | liquid | intermolecular forces
MSC:	Conceptual

	139.	Which of the following is indicative of the existence of strong intermolecular forces of attraction in a liquid?
A)	a very low boiling point	
B)	a very low viscosity	
C)	a very low vapor pressure	
D)	a very low heat of vaporization	
E)	a very low freezing point	

ANS:	C	PTS:	1	DIF:	Easy	REF:	10.8
KEY:	Chemistry | general chemistry | phases | liquid | intermolecular forces
MSC:	Conceptual

	140.	Which of the following intermolecular forces exist in all solid substances?
A)	Dispersion forces	
B)	Dipole-dipole forces	
C)	Covalent bonding	
D)	Hydrogen bonding	
E)	Ion-induced dipole forces	

ANS:	A	PTS:	1	DIF:	Easy	REF:	10.1
KEY:	Chemistry | general chemistry | phases | intermolecular forces	
MSC:	Conceptual

	141.	Consider the compounds CH3OH, CCl4, and CH3Br.  For each compound, list the strongest intermolecular force that operates within a sample of that compound.
A)	H-bonding is the strongest intermolecular force in CH3OH, dispersion is the strongest intermolecular force in CCl4, and dipole-dipole is the strongest intermolecular force in CH3Br	
B)	Dispersion is the strongest intermolecular force in CH3OH, dispersion is the strongest intermolecular force in CCl4, and dispersion is the strongest intermolecular force in CH3Br.	
C)	Ion-dipole is the strongest intermolecular force in CH3OH, Ion-dipole is the strongest intermolecular force in CCl4, and dipole-dipole is the strongest intermolecular force in CH3Br.	
D)	Dipole-induced dipole is the strongest intermolecular force in CH3OH, dispersion is the strongest intermolecular force in CCl4, and dipole-dipole is the strongest intermolecular force in CH3Br.	
E)	Ion-induced dipole is the strongest intermolecular force in CH3OH, dispersion is the strongest intermolecular force in CCl4, and H-bonding is the strongest intermolecular force in CH3Br.	

ANS:	A	PTS:	1	DIF:	Easy	REF:	10.1
KEY:	Chemistry | general chemistry | phases | intermolecular forces	
MSC:	Conceptual

	142.	In a standard phase diagram that plots temperature versus pressure, which one of the following statements is TRUE?
A)	Three phases coexist at equilibrium at any point along one of the lines that separate regions (areas) on the phase diagram.	
B)	Two phases coexist at equilibrium at the triple point on the phase diagram.	
C)	The gas-solid line ends at a critical point on the phase diagram, beyond which evaporation cannot occur.	
D)	The gas-liquid line ends at the critical point on the phase diagram, beyond which a gas cannot be compressed to form a liquid. 	
E)	In fact, all the above statements are false	

ANS:	D	PTS:	1	DIF:	Easy	REF:	10.9
KEY:	Chemistry | general chemistry | phases | phase transitions | phase diagram
MSC:	Conceptual