Chem exam final
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)
A)
Which ion among the following has the smallest radius?
Be2+
Which of these best describes the set of elements below? lead (Pb), vanadium, sulfur
main group metal, transiton metal, non-metal
q=
mc∆T
What adjective best describes the solid compound IF7?
molecular
When liquid bromine is cooled to form a solid, which of the following types of solid would it form?
molecular
Which of the following factors contributes to a low viscosity for a liquid?
spherical molecular shape
The phase diagram of a substance can be used to obtain the vapor pressure of that substance at a given temperature. T/F
true
The smallest repeating unit in a crystalline solid is known as its unit cell. T/F
true
Ti has __________ in its d orbitals.
two electrons
In which of the following processes is ∆H=∆E?
two moles of hydrogen iodide gas react to form hydrogen gas and iodine gas in a 40-L container
When solutions of barium chloride and ammonium phosphate react, which of the following is a spectator ion?
two of these
Which of the following is the correct formula for iron (III) oxide?
Fe2O3
Which one of the following types of radiation has the shortest wavelength, the greatest energy, and the highest frequency?
ultraviolet radiation
Which of the following should have the lowest boiling point?
N2
Which of the following forms an ionic solid?
NH4Cl
Sodium oxide combines violently with water. Which of the following gives the formula and bonding for sodium oxide?
Na2O, ionic compound
Which one of the following ionic compounds is most soluble in water?
Na2S
In the balanced molecular equation for the neutralization of sodium hydroxide with sulfuric acid, the products are:
Na2SO4 + 2H2O
Which of the following elements has the largest ionization energy?
Ne
Which of the following pairs is arranged with the particle of higher polarizability listed first?
Se2−, S2−
which of the following examples is not an example of a molecular solid?
SiO2
Which of the compounds below is not an example of a network solid?
SiO2(s)
n which of the following processes is ΔH =ΔE ?
Two moles of hydrogen iodide gas react to form hydrogen gas and iodine gas in a 40-L container.
Which of these best describes the set of elements below? potassium, chlorine, copper
alkali metal, non-metal, transition metal
Which of the following is NOT a network solid?
aluminum oxide, Al2O3(s)
Butane, C4H10, will behave most like an ideal gas:
at high temperature and low pressure
The assumptions of the kinetic-molecular theory are most likely to be correct under what conditions?
high temperature-low pressure
The strongest intermolecular interactions between ethyl alcohol (CH3CH2OH) molecules arise from
hydrogen bonding
Water molecules in ice are held in place by
hydrogen bonds
Gaseous HCl is known as
hydrogen chloride
Which if the following gases deviates most from ideal behavior?
hydrogen chloride
For which of the following elements (in their normal, stable, forms) would it be correct to describe the bonding as involving a "sea of electrons"?
lithium
enthalpy of vaporization equation
ln(P2-P1)=(∆H/R)[(1/T1)-(1/T2)]
Under what conditions will a real gas deviate most (act most differently) from ideal behavior?
low T and High P
Which of these is NOT a typical property of metallic solids?
low melting point
Adding heat will see the largest temperature increase in the liquid with the _________ specific heat
lowest
Give the number of possible orbitals in an H atom with the values: n=3, l=1
3
What value of the angular momentum quantum number, l, designates a 4f subshell?
3
what charge is present on a phosphate ion?
3-
A metal such with a face-centered cubic lattice will have ________________ atom(s) per unit cell.
4
How many subshells are there in an energy level with n = 4?
4
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:
4
A compound of sulfur and oxygen is 50% sulfur, 50% oxygen by weight. Sulfur and oxygen form another compound, in accordance with the law of multiple proportions. Which of the following is a likely composition for the second compound?
40 mass % sulfur 60 mass % oxygen
What is the sum of the stoichiometric coefficients on the left hand side of the following equation after it has been balanced with the smallest set of coefficients? PbO(s) + NH3(g) => N2(g) + H2O(l) + Pb(s)
5
Calculate the average mass, in grams, of an O2 molecule.
5.31 x 10-23
Calculate the mass percent of iodine in strontium iodate
58%
If a metal crystallizes in a primitive cubic lattice, each metal atom has ____ "nearest neighbors."
6
Which of the following has the lowest boiling point?
Ar
Which of the following would not be bent?
COS
In which of the following groups of substances would dispersion forces be the only significant factors in determining boiling points?
Cl2, Ne, CCl4
What is the formula of dichlorine heptaoxide?
Cl2O7
Which equation represents the number of atoms in a face-centered cubic unit cell?
#atoms=1/2(6)+1/8(8)
Which equation represents the number of atoms in a primitive cubic unit cell?
#atoms=1/8(8)
An electron in a 4p orbital can have a wave function with which of the following sets of quantum numbers, (n, l, ml, ms)?
(4, 1, -1, -1/2)
which quantities are variables and which are fixed in the following:Charles law, Boyles law, Avogrados law
(Charles)V/T= constant so T and V are variables with n and P fixed. (Boyles) P vs. T, (Avogrados) V vs. n
An atom in an octahedral hole is surrounded by _______ atoms.
6 ( This occurs in a simple cubic lattice, in a close cubic lattice it is 12)
Give the oxidation number of chromium in each of the following: (i) CrO3 (ii) [Cr2O7]2- (iii) Cr2(SO4)3
(i) +6 (ii)+6 (iii) +3
In nitromethane, CH3NO2, which has the connectivity shown in the formula, the formal charge on nitrogen is (complete the LDS to answer the question):
+1
Which is not a possible m1 value for a subshell that has the following: l=2
+3
what is the oxidation number for C in the chemical compound CaCO3?
+4
In thionyl chloride, Cl2SO (S is the central atom), the formal charge on oxygen and number of lone pairs on oxygen are, respectively, (assume all the atoms obey the octet rule
-1 and three
if the bond energies of X2 + C-X 194.6 KJ and to 297.7 KJ, respectively, and the bond energies of C-C and C=C are 338 KJ and 604 KJ, respectively, calculate the ∆E for the following reaction. C2H4+X2 -> C2H4X2 in kJ
-133.8
straight B presubscript 5 presuperscript 11 contains how many protons, electrons, and neutrons respectively?
. 5p, 5e, 6n
How many electrons can be described by the quantum numbers n = 3, l = 3, ml = -1?
0
1kpa=______ atm
0.01
r=
0.08206
According to molecular orbital theory, the bond order of B2+ is
0.5
According to MO theory how many unpaired electrons are present in the superoxide ion, O21-?
1
STP=___ atm
1
When identical particles pack in a simple cubic lattice, there is/are ____ particle(s) per unit cell.
1
What intermolecular force(s) is/are present in solid SO3? 1. London dispersion 2. dipole-dipole 3. hydrogen bonding
1 only
Which of the following characteristics apply to NCl3? 1. polar bonds 2. nonpolar molecule 3. triangular-planar molecular shape 4. sp2 hybridized
1 only
In molecular orbital theory, the bond orders in H2, H2+, and H2- are _____, respectively
1, 1/2, and 1/2
Which of the following statements concerning the cubic unit cell is/are CORRECT? 1. For cubic unit cells, three cell symmetries occur: primitive cubic, face-centered cubic, and body-centered cubic. 2. The cell edges of a cubic unit cell are all equal in length. 3. The corner angles of a cubic cell are 90°.
1,2,3
How many total moles of ions are released when the following sample dissolves in water? 0.382 mol K2HPO4
1.15 mol
How many electrons in an atom can have the quantum numbers n = 4, l = 2?
10
Which of the following does not produce a solution of HNO3 having a concentration of 0.2 M?
100mL of 0.100 M HNO3 solution is diluted to 200mL
If a metal crystallizes in a face-centered cubic lattice, each metal atom has ____ "nearest neighbors."
12
A metal with a body-centered cubic lattice will have ______ atom(s) per unit cell.
2
An atom located on a face of a unit cell is shared equally between ____ unit cells.
2
How many electrons are there in a filled 3px orbital?
2
For a gas, which two variables are directly proportional to one another? 1. T and n 2. P and n 3. P and T
2 and 3 only
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 in the center of each face. The unit cell contains how many anions and cations?
2 anions and 3 cations so it must be an M3X2 salt for charge neutrality
1 mol of STP =
22.4 L
An 56Fe3+ ion contains
26 protons, 30 neutrons and 23 electrons.
1 ATM = ___cm
76
1atm = ________torr
760
How many unit cells share an atom which is located at a corner (or lattice point) of a unit cell?
8
R=
8.314
Which of the following is the smallest hole in a closest-packed lattice of spheres? A) trigonal B) tetrahedral C) cubic D) octahedral E) none of these
A)
Which of the following should have the highest boiling point? A) Na2O B) HF C) NH3 D) N2 E) H2O
A)
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. What is the formula for the metal fluoride? A) MF2 B) M2F C) MF D) MF8 E) none of these
A)
Atoms that are sp3 hybridized form ____ pi bond(s). A) 0 B) 1 C) 2 D) 3 E) 4
A)
Identify the major attractive force in Ne. A) London dispersion forces B) dipole-dipole interactions C) hydrogen bonding D) ionic bonding E) none of these
A)
On the basis of your knowledge of bonding in liquids and solids, which of the following substances has the highest melting temperature? A) NaBr B) Br2 C) NO2 D) CF4 E) H2O
A)
Order the following from shortest to longest bond: C2, B2, H2, N2 A) H2, N2, C2, B2 B) N2, C2, B2, H2 C) C2, N2, H2, B2 D) C2, B2, H2, N2 E) none of these
A)
Select the correct molecular structure for I3 - . A) linear B) bent C) pyramidal D) tetrahedral E) none of these
A)
Select the correct molecular structure for PO3 3- . A) pyramidal B) tetrahedral C) square planar D) octahedral E) none of these
A)
The Cl-Kr-Cl bond angle in KrCl4 is closest to A) 90°. B) 109°. C) 120°. D) 150°. E) 360°
A)
What is the hybridization of C in the ion CN- ? A) sp B) sp2 C) sp3 D) dsp3 E) d2sp3
A)
Which of the following compounds has the highest boiling point? A) C2H6 B) CO C) H2 D) N2 E) Ne
A)
Which of the following compounds has the lowest boiling point? A) CH4 B) C2H6 C) C3H8 D) C4H10 E) C5H12
A)
Which of the following is paramagnetic? A) B2 B) C2 C) H2 D) N2 E) F2
A)
The formula of aluminum oxide is Al2O3 What is the formula of the ionic compound containing aluminum and permanganate ions?
Al(MnO4)3
Samples containing equal numbers of moles of H2 N2,O2, and He are placed into separate 1L containers at the same temperature. Assuming each gas behaves ideally, which container has the highest pressure?
All gases would exhibit same pressure
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) KCl C) NO2 D) H2O E) Cr
B)
A p-type semiconductor A) is made by doping host atoms with atoms having more valence electrons than the host. B) is made by doping host atoms with atoms having fewer valence electrons than the host. C) has electrons that lie close in energy to the conduction bands. D) two of these E) none of these
B)
Aluminum metal crystallizes in a face-centered cubic structure. What is the relationship between the radius of an Al atom (r) and the length of an edge of the unit cell (E)? A) r = E/2 B)r =E / sqrt(8) C) r =E (sqrt( 3 / 4)) D) r = 2E E) r = 4E
B)
Consider the following molecules. I. BF3 II. CHBr3 (C is the central atom.) III. Br2 IV. XeCl2 V. CO VI. SF4 Select the molecule(s) that fit the given statement. 5. These molecules have a zero net dipole moment. A) III, V B) I, III, IV C) III, IV, V D) I, III, IV, VI E) none of them
B)
Draw the Lewis structures of the molecules below, and use them to answer the following questions. I. BH3 II. NO2 III. SF6 IV. O3 V. PCl5 9. Which of these molecules show resonance? A) I, II B) II, IV C) II, V D) III, IV E) III, V
B)
Identify the major attractive force in H2S. A) London dispersion forces B) dipole-dipole interactions C) hydrogen bonding D) ionic bonding E) none of these
B)
In the unit cell of sphalerite, Zn2+ ions occupy half the tetrahedral holes in a face-centered cubic lattice of S2- ions. What is the number of formula units of ZnS in the unit cell? A) 5 B) 4 C) 3 D) 2 E) 1
B)
The molar volume of a certain form of solid lead is 18 cm3 /mol. Assuming cubic closest-packed structure, determine the following. 67. The number of Pb atoms per unit cell A) 3 B) 4 C) 10 D) 12 E) 14
B)
The resistance of a liquid to an increase in its surface area is called A) capillary action. B) surface tension. C) vapor pressure D) viscosity. E) none of these
B)
What is the net number of face-centered atoms contained in a face-centered cubic unit cell? A) 1 B) 3 C) 4 D) 6 E) none of these
B)
Which ion is planar? A) PF4+ B) CO32- C) SO32- D) ClO4- E) SCl5-
B)
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)
B)
Which of the following compounds has the highest boiling point? A) CH4 B) H2O C) NF3 D) O2 E) He
B)
Which of the following has the shortest N-O bond? A) NO3- B) NO+ C) N2 D) NO2- E) none of these
B)
Which of the following molecules contains a nitrogen atom that is sp2 hybridized? A) NH3 B) NO3- C) N2 D) HCN E) C2N2
B)
Which of the following statements is correct? A) A triple bond is composed of two sigma bonds and one pi bond. B) sigma bonds result from the head-to-head overlap of atomic orbitals. C) Free rotation may occur about a double bond. D) pi bonds have electron density on the internuclear axis. E) More than one of these statements are correct.
B)
Which of the following statements is(are) false? I. The hexagonal closest-packed structure is ABAB.... 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 was a simple cubic array. A) I only B) II only C) II, III only D) I, IV E) II, III, IV
B)
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.
B)
Which statement is correct? A) H2O is linear. B) The molecule ClO2 cannot be accurately described by a Lewis structure consistent with the octet rule. C) The diatomic molecule Cl2 is an example of a polar molecule. D) The bonds in LiF have a more covalent character than those in F2. E) none of these
B)
Of the following elements, which has the lowest first ionization energy?
Ba
Which of the following elements has the greatest (most exothermic) electron affinity?
Br
As the bond order of a bond increases, its bond energy ______ and its bond length ______. A) increases, increases B) decreases, decreases C) increases, decreases D) decreases, increases
C)
Doping Se with As would produce a(n) __________ semiconductor with __________ conductivity compared to pure Se. A) n-type, increased B) n-type, decreased C) p-type, increased D) p-type, decreased E) intrinsic, identical
C)
How many of the following molecules and ions are linear? NCl3 NH4 + SCN- CO2 NO2 - A) 0 B) 1 C) 2 D) 3 E) 4
C)
Identify the major attractive force in HF. A) London dispersion forces B) dipole-dipole interactions C) hydrogen bonding D) ionic bonding E) none of these
C)
If four orbitals on one atom overlap four orbitals on a second atom, how many molecular orbitals will form? A) 1 B) 4 C) 8 D) 16 E) none of these
C)
Of the following, which molecule has the largest bond angle? A) SO3 B) SF2 C) HCN D) H2S E) PF3
C)
The elements of Group 5A, the nitrogen family, form compounds with hydrogen that have the boiling points listed below. SbH3 -17°C, AsH3 -55°C, PH3 -87°C, NH3 -33°C The first three elements 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.
C)
The molar volume of a certain form of solid lead is 18 cm3 /mol. Assuming cubic closest-packed structure, determine the following. The radius of a Pb atom A) 1.74 pm B) 17.4 pm C) 174 pm D) 1740 pm E) none of these
C)
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
C)
What is the hybridization of S in the molecule H2S? A) sp B) sp2 C) sp3 D) dsp3 E) d2sp3
C)
What type of structure does the XeOF2 molecule have? A) pyramidal B) tetrahedral C) T-shaped D) trigonal planar E) octahedral
C)
Which of the following has two pi bonds? A) C2H6 B) C2H4 C) C2H2 D) at least two of these E) none of these
C)
Which of the following statements about the CO3 2- ion is false? A) The orbitals on the carbon atom are sp2 hybridized. B) The ion is expected to be diamagnetic. C) One C-O bond is shorter than the others. D) The ion has a total of 24 electrons. E) It has a planar molecular geometry
C)
Which one of the following substances would you expect to be a non-electrolyte in aqueous solution?
CH3CH2OH
Which of the following week soluble compounds does not conduct an appreciable current in aqueous solution by means of ion movement?
CH3CH2OH (ethyl alcohol)
An unknown gas Q diffuses at a RATE 1.65 times faster than that of propane, C3H8. Which of these are most likely to be Q?
CH4
Which of the following would have a higher rate of effusion than C2H2?
CH4
Which of the following molecules has no dipole moment?
CO2
what is the order of increasing rate of effusion for the following gases? At, CO2, He, N2
CO2<Ar<N2<He
In the reaction: Cu(s) + 2Ag+(aq) => Cu2+(aq)+ 2Ag(s) the reducing agent is
Cu(s)
For which of the following diatomic molecules would the bond order become greater if an electron were removed, that is, if the molecule were converted to the positive ion in its ground state? A) B2 B) C2 C) P2 D) F2 E) Na2
D)
How many electrons are involved in pi bonding in benzene, C6H6? A) 12 B) 30 C) 3 D) 6 E) 18
D)
Identify the major attractive force in CaF2. A) London dispersion forces B) dipole-dipole interactions C) hydrogen bonding D) ionic bonding E) none of these
D)
In cubic closest-packed solids, what percentage of space is occupied by the spheres? A) 43.8% B) 52.4% C) 68.0% D) 74.0% E) none of these
D)
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. What is the number of Na+ ions in the unit cell? A) 2 B) 4 C) 6 D) 8 E) none of these
D)
The molar volume of a certain form of solid lead is 18 cm3 /mol. Assuming cubic closest-packed structure, determine the following.The volume of a single cell A) 1.20 x 102 pm3 B) 1.20 x 104 pm3 C) 1.20 x 106 pm3 D) 1.20 x 108 pm3 E) none of these
D)
The molecule XCl5 - has a square pyramidal shape. Which of the following atoms could be X? A) O B) P C) Xe D) S E) At least two of these atoms could be X.
D)
What is the hybridization of I in the molecule ICl3? A) sp B) sp2 C) sp3 D) dsp3 E) d2sp3
D)
What is the hybridization of the central atom in SF4? A) sp B) sp2 C) sp3 D) dsp3 E) d2sp3
D)
Which of the following is polar? A) SiF4 B) XeF2 C) BCl3 D) NBr3 E) SBr6
D)
Which of the following is the correct order of boiling points for NaNO3, CH3OH, C2H6, and Ne? A) Ne < CH3OH < C2H6 < NaNO3 B) NaNO3 < CH3OH < C2H6 < Ne C) Ne < C2H6 < NaNO3 < CH3OH D) Ne < C2H6 < CH3OH < NaNO3 E) C2H6 < Ne < CH3OH < NaNO3
D)
Which of the following shows these molecules in order from most polar to least polar? A) CH4 > CF2Cl2 > CF2H2 > CCl4 > CCl2H2 B) CH4 > CF2H2 > CF2Cl2 > CCl4 > CCl2H2 C) CF2Cl2 > CF2H2 > CCl2H2 > CH4 = CCl4 D) CF2H2 > CCl2H2 > CF2Cl2 > CH4 = CCl4 E) CF2Cl2 > CF2H2 > CCl4 > CCl2H2 > CH
D)
Which of the following statements is true about the vapor pressures of methane (CH4) and ammonia (NH3)? A) The vapor pressure of ammonia is greater than the vapor pressure of methane because ammonia is polar and methane is nonpolar. B) The vapor pressure of ammonia is less than the vapor pressure of methane because ammonia is nonpolar and methane is polar. C) The vapor pressure of methane is greater than the vapor pressure of methane because methane has more hydrogen bonding than ammonia. D) The vapor pressure of ammonia is equal to the vapor pressure of methane. E) None of these statements is true.
D)
Which substance involves no intermolecular forces except London dispersion forces? A) K B) H2S C) NaF D) H2 E) HCl
D)
which statement is true concerning atomic Spectra?
During the production emission Spectra, electrons move from higher to lower levels
Select the correct molecular structure for SF4. A) linear B) bent C) pyramidal D) tetrahedral E) none of these
E)
What is the hybridization of the central atom in IF5? A) sp B) sp2 C) sp3 D) dsp3 E) d2sp3
E)
What is the hybridization of the central atom in SF6? A) sp B) sp2 C) sp3 D) dsp3 E) d2sp3
E)
Which of the following has an incomplete octet in its Lewis structure? A) SO2 B) ICl C) SF2 D) F2 E) NO
E)
Which of the following is paramagnetic? A) O2- B) O2+ C) O2 D) N2 E) At least two of these are paramagnetic.
E)
Which of the following species has the largest dissociation energy? A) O2 B) O2- C) O2 2- D) O2+ E) O2 2+
E)
Which of the following statements is incorrect? A) Ionic bonding results from the transfer of electrons from one atom to another. B) Dipole moments result from the unequal distribution of electrons in a molecule. C) The electrons in a polar bond are found nearer to the more electronegative element. D) A molecule with very polar bonds can be nonpolar. E) Linear molecules cannot have a net dipole moment.
E)
Which of the following statements is true about p-type silicon? A) It is produced by doping Si with P or As. B) Electrons are the mobile charge carriers. C) It does not conduct electricity as well as pure Si. D) All are true. E) None is true.
E)
Which of the following statements is true? A) Electrons are never found in an antibonding MO. B) All antibonding MOs are higher in energy than the atomic orbitals of which they are composed. C) Antibonding MOs have electron density mainly outside the space between the two nuclei. D) None of these statements is true. E) Two of these statements are true.
E)
formula to calculate energy of photon
E=h*c/wavelength
Which of the following statements about the closest packing of spheres in binary ionic solids is false?
For spheres of a given diameter, tetrahedral holes are larger than octahedral holes.
Which one of the following reactions occuring at 25°C is the formation reaction of H2SO4 (l)?
H2(g)+ S(s) +2O2(g) -> H2SO4
which of the following is not a weak electrolyte?
HNO3
Which of the following liquids has the greatest viscocity?
HOCH2CH2OH
In which atom or ion are the 3s and 3p orbitals equal in energy?
He+1
Which statement is not correct?
Heat and work are state functions
Which of the following is a correct statement?
Hydrobromic acid is a strong acid
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 a simple cubic (primitive) structure, there would be one atom (net) for each unit cell. IV. Atoms in a solid consisting of only one element would have six nearest neighbors if the crystal structure were a simple cubic array.
II
Consider the reaction: C2H5OH(l) + 3O2(g) → 2CO2(g) + 3H2O(l); ΔH = -1.37 × 103 kJ Consider the following propositions: I. The reaction is endothermic II. The reaction is exothermic. III. The enthalpy term would be different if the water formed was gaseous. Which of these propositions is (are) true?
II, III
which of the following ionic solids would have the highest melting point?
KF
In frozen methane, CH4, the molecules of methane are held in place by
London dispersion forces
Octane is a component of fuel used in internal combustion engines. The dominant intermolecular forces in octane are
London dispersion forces
Which notion is incorrect?
London dispersion forces weaken in the order Xe < Kr < Ar
density equation.
M=drt/p (moles pee under dirt)
A certain metal fluoride crystallizes in such a way that the fluoride ions occupy simple cubic lattice sites, while the metal ions occupy the body centers of half the unit cells. The formula for the metal fluoride is:
MF2
Which of the following has the smallest radius?
P
Which of the following elements is the least electronegative?
Rb
what stable monatomic ions do rubidium (Z=37) and selenium (Z=34) form?
Rb+ and Se2-
Which of the following atoms should have the smallest polarizability?
S
Consider the ionization energy (IE) of the magnesium atom. Which of the following is not true?
The IE of Mg is lower than that of sodium
Which of the following is not an assumption of the kinetic molecular theory for a gas?
The average velocity of the gas particles is directly proportional to the mass of the gas particles at constant temperature
When a nonpolar liquid displays a convex meniscus, which of the following explains this behavior?
The cohesive forces are stronger than the adhesive forces to the glass
One of the main advantages of hydrogen as fuel is that:
The only product of hydrogen combustion is water
Which is not true for an endothermic reaction?
The products have a lower enthalpy than the reactants.
Which of the following statements is(are) correct?
The system does work on the surroundings when an ideal gas expands against a constant external pressure.
Which one of the following statements about solid Cu (face-centered cubic unit cell) is incorrect?
There are two atoms per unit cell.
In the two reactions below, which atom is oxidized? Zn(s)+H2SO4(aq) -> ZnSO4(aq)+ H2(g) H2O2+CaS -> CaSO4+H2O (not balanced)
Zn and S
At room temperature, CH3F is expected to be
a gas
When a water molecule forms a hydrogen bond with another water molecule, which atoms are involved in the interaction?
a hydrogen from one molecule and an oxygen from the other molecule
Consider an isolated N-C bond in an organic compound. Based on the electronegativities of the two elements, which of the following best describes the net charge on the carbon atom?
a partial positive charge
Which set of these comparisons is INCORRECT? (More stable means it has a more negative energy.) a) The 1s orbital in H is more stable than the 1s orbital in He+ b) The 2s orbital in He atom is less stable than the 2s orbital in He+ c) The 2s subshell in Li is more stable than the 2p subshell in Li
a)only
Choose the answer which best describes what type of solid the elements and compounds below form, in that order. Kr CH3OH BaBr2 diamond
atomic, molecular, ionic, network
Which of the following indicate the greatest pressure? a. 1 ATM b. 777 torr c. 5.5 mm Hg d. 1000Pa e. 12 psi
b.
Predict the approximate bond angles in SF3+ using the VSEPR theory.
between 90° and 109°
Which one of the following properties is least characteristic of typical metals?
brittleness
Which of the following is NOT a network solid?
buckminster fullerene, C60(s)
Quartz (SiO2) is a solid with a melting point of 1550°C. The bonding in quartz is best described as
covalent bonding
The molecular orbital (band) energy level diagram of __________ exhibits large gaps between filled energy levels
diamonds
What types of forces exist between molecules of CO2?
dispersion forces only.
According to the kinetic molecular theory, kinetic energy is conserved in a collision. We say that these collisions are
elastic
A(n) ________ is a pure substance that is composed of only one type of atom.
element
Dipole-dipole forces result from instantaneous dipoles that form in atoms and nonpolar molecules. T/F
false
Ice is an example of a molecular solid that conducts an electric current because of it strong hydrogen bonding.T/F
false
In cubic closest packing, the unit cell is body-centered cubic. T/F
false
Most atomic solids have low melting points.T/F
false
Most metals occur as ionic solids. T/F
false
The energy of a hydrogen bond is greater than that of a typical covalent bond. T/F
false
The two main components of the internal energy of a substance are the vibrational energy and rotational energy. T/F
false
Fe has __________ that is (are) unpaired in its d orbitals
four electrons
which of the following is paired incorrectly?
gold metal- simple cubic unit cell
Graphene was first prepared by removing layers from _________.
graphite
if you double the volume of gas, you _________ the pressure
halve
According to the band theory as applied to metallic bonding, what set of these statements is TRUE? i) the bonds between neighboring metal atoms can be described as localized electron pair bonds ii) the valence electrons of representative metals are free to move within the solid leading to thermal conductivity iii) the electrical conductivity of metallic solids decreases with increasing temperature
ii) and iii) only
Which statement or statements concerning metals is INCORRECT? i) in the solid state, metals conduct electric current uniformly in all directions ii) the bonding in most metallic solids is mono-directional iii) the "electron sea model" explains electrical conductivity of metals by assuming that their valence electrons move freely within the lattice
iii) only
The bonds between hydrogen and oxygen within a water molecule can be characterized as __________
intramolecular forces (not inter)
Which of the following is not an example of a network covalent solid?
iron
The net number of spheres in the face-centered cubic unit cell is 4. T/F
true
given that the energy of a hydrogen atom is given by the equation: E=(-22.7 x 10^-19 J)/n^2. which relaxation will give the rise to the least energetic photon?
n=6,n=5
The ion NO2- is named
nitrite ion
Methyl alcohol (CH3OH), ethyl alcohol (CH3CH2OH), ethylene glycol (HOCH2CH2OH), and sucrose (C12H22O11) are commonly classified as
non-electroytes
Which best explains the following trend? Element b.p. (K) He 4 Ne 25 Ar 95 Kr 125 Xe 170
none of these
Methyl alcohol (CH3OH), ethyl alcohol (CH3CH2OH), ethylene glycol (HOCH2CH2OH), and sucrose (C12H22O11) are commonly classified as
nonelectrolytes
Arrange the three common unit cells in order from least dense to most dense packing.
primitive cubic < body-centered cubic < face-centered cubic
∆E=
q + w
heat required to vaporize
q=m(∆H)
Under which of the following sets of conditions will a sample of a real gas deviate most from ideal behavior?
strong interparticle attractions, low temperature, high pressure
what is the name of H2SO4?
sulfuric acid
Which of the following properties is a measure of the energy needed to increase the surface area of a liquid?
surface tension
What is responsible for capillary action, a property of liquids?
surface tension of liquid, attractive forces between the liquid and the capillary material
Graham's law states that
the diffusion-effusion rate of a gas is inversely proportional to the square root of the mass of its particles.
All of the following are true except
the energies of subshell in the shells (energy levels) of a hydrogen atom vary as s<p<d, etc.
Which of the following best describes the bonding between atoms in metals.
the valence electrons of a given metal atom are delocalized (spread)over all of the atoms in the piece of metal
what is the name for the lowest layer of the atmosphere, which is most influenced by human activities?
troposphere
Intermolecular forces are weaker than intramolecular bonds. T/F
true
Liquids with large intermolecular forces tend to have high surface tension. T/F
true
Silicates are network solids which contain Si-O-Si bridges that make up many rocks, clays and ceramics. T/F
true
Which of the following terms refers to the resistance of a liquid to flow?
viscosity
the number of moles don't change so ___________ doesn't change
volume
The ductility of copper allows it to be pulled into a _________.
wire
In which case is the bond polarity incorrect?
δ+Cl-Iδ-
