Honors Chemistry – Chapter 9 Review Packet Name______

Mr. Citta Date______

1.The basis of the VSEPR model of molecular bonding is ______.

a.regions of electron density on an atom will organize themselves so as to maximize s-character

b.regions of electron density in the valence shell of an atom will arrange themselves so as to maximize overlap

c.atomic orbitals of the bonding atoms must overlap for a bond to form

d.electron pairs in the valence shell of an atom will arrange themselves so as to minimize repulsions

e.hybrid orbitals will form as necessary to, as closely as possible, achieve spherical symmetry

2.According to VSEPR theory, if there are 5 pairs of electrons in the valence shell of an atom, they will be arranged in a(n) ______geometry.

a.octahedral

b.linear

c.tetrahedral

d.trigonal planar

e.trigonal bipyramidal

3.According to VSEPR theory, if there are 4 pairs of electrons in the valence shell of an atom, they will be arranged in a(n) ______geometry.

a.octahedron

b.straight line

c.tetrahedron

d.trigonal plane

e.trigonal bipyramid

4.In counting the electron domains around the central atom in VSEPR theory, a ______is not included.

a.nonbonding pair of electrons

b.single covalent bond

c.core level electron pair

d.double covalent bond

e.triple covalent bond

5.The molecular geometry of the H3O+ ion is ______.

a.linear

b.tetrahedral

c.bent

d.trigonal pyramidal

e.octahedral

6.The molecular geometry of the SiH2Cl2 molecule is ______.

a.trigonal planar

b.tetrahedral

c.trigonal pyramidal

d.octahedral

e.T-shaped

7.The molecular geometry of the PHCl2 molecule is ______.

a.bent

b.trigonal planar

c.trigonal pyramidal

d.tetrahedral

e.T-shaped

8.The molecular geometry of the SF2 molecule is ______.

a.linear

b.bent

c.trigonal planar

d.tetrahedral

e.octahedral

9.The molecular geometry of the right-most carbon in the molecule below is ______.

a.trigonal planar

b.trigonal bipyramidal

c.tetrahedral

d.octahedral

e.T-shaped

10. The central iodine atom in the ICl- ion, has ___ nonbonded electron

4

pairs and ___ bonded electron pairs in its valence shell.

a.2,2

b.3,1

c.1,3

d.3,2

e.2,4

11.An electron domain is a ______.

1. lone pair

2. single bond

3. double bond

4. triple bond

5. central atom

a.1 or 2

b.1, 2, 3, or 4

c.5 only

d.2, 3, or 4

e.1 or 5

12.Of the molecules below, _____ is polar.

a.SbF5

b.AsH3

c.I2

d.SF6

e.CH4

13.Of the molecules below, only _____ is nonpolar.

a.CO2

b.H2O

c.NH3

d.HCl

e.TeCl2

14.Of the molecules below, only _____ is nonpolar.

a.BF3

b.NF3

c.IF3

d.PBr3

e.BrCl3

15.Of the following molecules, only _____ is polar.

a.CCl4

b.BCl3

c.NCl3

d.BeCl2

e.Cl2

  1. The molecular geometry of the CHF3 molecule is ______, and the molecule is ______.

a.trigonal pyramidal, polar

b.tetrahedral, nonpolar

c.seesaw, nonpolar

d.tetrahedral, polar

e.seesaw, polar

17.According to valence bond theory, which orbitals overlap in the formation of the bond in HBr?

a.1s on H and 4p on Br

b.1s on H and 4s on Br

c.1s on H and 3p on Br

d.2s on H and 4p on Br

e.2s on H and 3p on Br

18.The electron-domain geometry of a carbon-centered compound is tetrahedral. The hybridization of the central carbon atom is _____.

a.sp

b.sp2

c.sp3

d.sp3d

e.sp3d2

19.Generally, a molecule in which the central atom is sp2 hybridized will have a/an ______electron-domain geometry.

a.octahedral

b.linear

c.trigonal planar

d.trigonal bipyramidal

e.tetrahedral

20.The hybridization of the carbon atom in carbon dioxide is _____.

a.sp

b.sp2

c.sp3

d.sp3d

e.sp3d2

21.The hybridization of the central atom in the XeF4 molecule is _____.

a.sp

b.sp2

c.sp3

d.sp3d

e.sp3d2

22.The sp3d2 atomic hybrid orbital set accommodates _____ electron pairs.

a.2

b.3

c.4

d.5

e.6

23.The hybridizations of bromine in BrF5 and of arsenic in AsF5 are _____ and _____, respectively.

a.sp3, and sp3d

b.sp3d, and sp3d2

c.sp3d, and sp3

d.sp3d2, and sp3d

e.sp3d2, and sp3d2

24.There are _____ unhybridized p atomic orbitals in an sp-hybridized carbon atom.

a.0

b.1

c.2

d.3

e.4

25.When three atomic orbitals are mixed to form hybrid orbitals, how many hybrid orbitals are formed?

a.one

b.six

c.three

d.four

e.five

26.In the overall process of hybrid orbital formation, the purpose of promoting one or more electrons is to ______.

a.increase the number of atomic orbitals

b.increase the number of unpaired electrons

c.increase the number of hybrid orbitals

d.make sure that every atomic orbital is occupied prior to hybridization

e.make sure that all of the electrons in atomic orbitals are unpaired prior to hybridization

27.A typical triple bond ______.

a.consists of one  bond and two  bonds

b.consists of three shared electrons

c.consists of two  bonds and one  bond

d.consists of six shared electron pairs

e.is longer than a single bond

28.In order to exhibit delocalized  bonding, a molecule must have ______.

a.at least two  bonds

b.at least two resonance structures

c.at least three  bonds

d.at least four atoms

e.trigonal planar electron domain geometry

29.The carbon-carbon  bond in ethylene, CH2CH2, results from the overlap of ______.

a.sp hybrid orbitals

b.sp3 hybrid orbitals

c.sp2 hybrid orbitals

d.s atomic orbitals

e.p atomic orbitals

30.In order for rotation to occur about a double bond, ______.

a.the  bond must be broken

b.the  bond must be broken

c.the bonding must be delocalized

d.the bonding must be localized

e.the  and  bonds must both be broken

31.A typical triple bond consists of ______.

a.three sigma bonds

b.three pi bonds

c.one sigma and two pi bonds

d.two sigma and one pi bond

e.three ionic bonds

32.The N-N bond in H-N=N-H consists of ______.

a.one  bond and one  bond

b.one  bond and two  bonds

c.two  bonds and one  bond

d.two  bonds and two bonds

e.one  bond and no  bonds

33.There are __  and __  bonds in the H2C=C=CH2 molecule.

a.4 and 2

b.6 and 4

c.2 and 2

d.2 and 6

e.6 and 2

34.The hybridization of the central carbon in H2C=C=CH2 is _____.

a.sp

b.s2p

c.sp2

d.s2p2

e.sp3d

35.The hybridization of the carbon atom in carbon dioxide is _____.

a.sp3

b.sp2

c.sp

d.sp2d

e.sp2d2

36.Electrons in ___ bonds remain localized between two atoms. Electrons in ___ bonds can become delocalized between more than two atoms.

a.pi, sigma

b.sigma, pi

c.pi, pi

d.sigma, sigma

e.ionic, sigma

37.Structural changes around a double bond in the ____ portion of rhodopsin molecule trigger the chemical reactions that result in vision.

a.protein

b.opsin

c.retinal

d.cones

e.rods

38.The bond order of any molecule containing equal numbers of bonding and antibonding electrons is ______.

a.0

b.1

c.2

d.3

e.1/2

39.Of the following, only _____ has unpaired electron(s).

a.C2

b.N2

c.F2

d.O2

e.Li2

40.Based on molecular orbital theory, there are ______unpaired electrons in the OF+ ion.

a.0

b.3

c.1

d.2

e.1/2

41.In molecular orbital theory, the bond orders in H2, H2+, and H2- are _____, respectively

a.1, 0, and 0

b.1, 1/2, and 0

c.1, 0, and 1/2

d.1, 1/2, and 1/2

e.1, 2, and 0

42. In molecular orbital theory, the bond order in the He+ ion is _____.

2

a.0

b.1/2

c.1

d.3/2

e.2

43.According to molecular orbital theory, the bond order of the N2 molecule is _____.

a.0

b.1

c.2

d.3

e.5

44.Using molecular orbital theory, the bond order of the Be Be bond in the Be2 molecule is _____.

a.0

b.1

c.2

d.3

e.4

45.A molecular orbital can accommodate a maximum of _____ electron(s).

a.one

b.two

c.four

d.six

e.twelve

46.An antibonding MO ______the corresponding bonding MO.

a.is always lower in energy than

b.can accommodate more electrons than

c.can accommodate fewer electrons than

d.is always higher in energy than

e.is always degenerate with

47.The more effectively two atomic orbitals overlap, ______.

a.the more bonding MOs will be produced by the combination

b.the higher will be the energy of the resulting bonding MO and the lower will be the energy of the resulting antibonding MO

c.the higher will be the energies of both bonding and antibonding MOs that result

d.the fewer antibonding MOs will be produced by the combination

e.the lower will be the energy of the resulting bonding MO and the higher will be the energy of the resulting antibonding MO

48.The order of MO energies in B2, C2, and N2 (2p > 2p), is different from the order in O2, F2, and Ne2 (2p < 2p). This is due to

a.less effective overlap of p orbitals in O2, F2, and Ne2

b.the more metallic character of boron, carbon and nitrogen as compared to oxygen, fluorine, and neon

c.greater 2s-2p interaction in O2, F2, and Ne2

d.greater 2s-2p interaction in B2, C2, and N2

e.less effective overlap of p orbitals in B2, C2, and N2

49.In molecules containing alternating single and double bonds, the  bonds are said to be _____.

a.atomic

b.occupied

c.conjugated

d.dyed

e.hybridized

50.Of the following, _____ is false regarding -carotene.

a.It contains 11 conjugated double bonds.

b.It is the substance chiefly responsible for the bright orange color of carrots.

c.The human body converts it to vitamin-A.

d.It has a very large HOMO-LUMO gap.

e.Its ã electrons are extensively delocalized.