Chem exam 3!!!

(i) PCl3 (ii) CCl4 (iii) TeCl4 (iv) XeF4 (v) SF6 28) Which of the molecules has a see-saw shape? A) (i) B) (ii) C) (iii) D) (iv) E) (v)

(iii) TeCl4

Consider the following electron configurations to answer the questions that follow 1. 1s2 2s1 2. 1s2 2s2 3. 1s2 2s2 2p3 4. 1s2 2s2 2p4 5. 1s2 2s2 2p6 The electron configuration of the atom with the most negative electron afinity is

(iv)

(i) PCl3 (ii) CCl4 (iii) TeCl4 (iv) XeF4 (v) SF6 43) In which of the molecules is the central atom sp3d2 hybridized? A) (i) and (ii) B) (iii) only C) (iii) and (iv) D) (iv) and (v) E) (v) only

(iv) XeF4 (v) SF6

Hydrogen is unique among the elements because 1. it is not really a member of any particular group 2. Its electron is not at all shielded from its nucleus. 3. It is the lightest element 4. It is the only element to exist at room temperature as a diatomic gas 5. It exhibits some chemical properties similar to those of groups 1A and 7A

1, 2, 3, 5

24) The angles between sp2 orbitals are ________. A) 45° B) 180° C) 90° D) 109.5° E) 120°

120

74) A molecular orbital can accommodate a maximum of ________ electron(s). A) 1 B) 2 C) 4 D) 6 E) 12

2

16) Oxides of the active metals combine with water to form __________. A) metal hydroxides D) oxygen gas B) metal hydrides E) water and a salt C) hydrogen gas

A

The list that correctly indicates the order of metallic character is __________. A) Sr > Ca > Mg B) F > Cl > Br C) C > Ge > Si D) Li > Na > K E) O > Se > S

A

__________ have the lowest first ionization energies of the groups listed. A) Alkali metals B) Transition elements C) Halogens D) Alkaline earth metals E) Noble gases

A

the first ionization energies of the elements _____ as you go from left to right across a period of the periodic table, and _____ as you go from bottom to top. A) increase, increase B)increase, decrease C)decrease, increase D)decrease decrease

A

53) Using the table of bond dissociation energies, the for the following reaction is __________ kJ. A) -359 B) -223 C) 359 D) 223 E) 208

A) -359

27) What is the maximum number of double bonds that a hydrogen atom can form? A) 0 B) 1 C) 2 D) 3 E) 4

A) 0

39) The formal charge on carbon in the molecule below is __________. A) 0 B) +1 C) +2 D) +3 E) -1

A) 0

67) 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

A) 0

7) How many unpaired electrons are there in the Lewis structures of N3- a ion? A) 0 B) 1 C) 2 D) 3 E) This cannot be predicted.

A) 0

8) How many unpaired electrons are there in an O2- ion? A) 0 B) 1 C) 2 D) 3 E) This cannot be predicted.

A) 0

80) Based on 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

A) 0

25) For molecules with only one central atom, how many lone pairs on the central atom guarantees molecular polarity? A) 1 B) 2 C) 1 or 2 D) 3 E) 1 or 3

A) 1

47) How many different types of resonance structures can be drawn for SO3^2- the ion where all atoms satisfy the octet rule? A) 1 B) 2 C) 3 D) 4 E) 5

A) 1

50) Given that the average bond energies for C-H and C-Br bonds are 413 and 276 kJ/mol, respectively, the heat of atomization of bromoform is __________ kJ/mol. A) 1241 B) 689 C) -689 D) 1378 E) -1378

A) 1241

25) There are ________ σ and ________ π bonds in the H—C≡C—H molecule. A) 3 and 2 B) 3 and 4 C) 4 and 3 D) 2 and 3 E) 5 and 0

A) 3 and 2

16) The principal quantum number of the electrons that are lost when tungsten forms a cation is __________. A) 6 B) 5 C) 4 D) 3 E) 2

A) 6

20) Of the molecules below, only ________ is nonpolar. A) BF3 B) NF3 C) IF3 D) PBr3 E) BrCl3

A) BF3

4) Which of the following does not have eight valence electrons? A) Ca B) Rb+ C) Xe D) Br- E) All of the above have eight valence electrons.

A) Ca

44) A valid Lewis structure of __________ cannot be drawn without violating the octet rule. A) ClF3 B) PCl3 C) SO3 D) CCl4 E) CO2

A) ClF3

3) Based on the octet rule, magnesium most likely forms a __________ ion. A) Mg2+ B) Mg2- C) Mg6- D) Mg6+ E) Mg-

A) Mg2+

22) Which two bonds are most similar in polarity? A) O--F and C--F B) B--F and Cl--F C) Al--Cl and I--Br D) I--Br and Si-Cr E) Cl--Cl and Be--Cl

A) O--F and C--F

17) Of the atoms below, __________ is the least electronegative. A) Rb B) F C) Si D) Cl E) Ca

A) Rb

47) Why don't we draw double bonds between the Be atom and the Cl atoms in ? A) That would give positive formal charges to the chlorine atoms and a negative formal charge to the beryllium atom. B) There aren't enough electrons. C) That would result in more than eight electrons around beryllium. D) That would result in more than eight electrons around each chlorine atom. E) That would result in the formal charges not adding up to zero.

A) That would give positive formal charges to the chlorine atoms and a negative formal charge to the beryllium atom.

19) What is the electron configuration for the Fe2+ ion? A) [Ar]4s^0 3d^6 B) [Ar] 4s^2 3d^4 C) [Ar] 3s^0 3d^8 D) [Ar] 4s^2 3d^8 E) [Ar] 4s^6 3d^2

A) [Ar]4s^0 3d^6

49) Bond enthalpy is __________. A) always positive B) always negative C) sometimes positive, sometimes negative D) always zero E) unpredictable

A) always positive

48) A typical triple bond ________. A) consists of one σ bond and two π bonds B) consists of three shared electrons C) consists of two σ bonds and one π bond D) consists of six shared electron pairs E) is longer than a single bond

A) consists of one σ bond and two π bonds

14) For a given arrangement of ions, the lattice energy increases as ionic radius __________ and as ionic charge __________. A) decreases, increases B) increases, decreases C) increases, increases D) decreases, decreases E) This cannot be predicted.

A) decreases, increases

Atomic radius generally increases as we move __________. A) down a group and from right to left across a period B) up a group and from left to right across a period C) down a group and from left to right across a period D) up a group and from right to left across a period E) down a group; the period position has no effect

A) down a group and from right to left across a period

46) Valence bond theory does not address the issue of ________. A) excited states of molecules B) molecular shape C) covalent bonding D) hybridization E) multiple bonds

A) excited states of molecules

69) In comparing the same two atoms bonded together, the ________ the bond order, the ________ the bond length, and the ________ the bond energy. A) greater, shorter, greater B) greater, greater, greater C) greater, longer, greater D) greater, greater, smaller E) smaller, greater, greater

A) greater, shorter, greater

54) In a typical multiple bond, the σ bond results from overlap of ________ orbitals and the π bond(s) result from overlap of ________ orbitals. A) hybrid, atomic B) hybrid, hybrid C) atomic, hybrid D) hybrid, hybrid or atomic E) hybrid or atomic, hybrid or atomic

A) hybrid, atomic

16) Using the VSEPR model, the molecular geometry of the central atom in KrF2 is ________. A) linear B) trigonal planar C) tetrahedral D) bent E) trigonal pyramidal

A) linear

4) The molecular geometry of the CS2 molecule is ________. A) linear B) bent C) tetrahedral D) trigonal planar E) T-shaped

A) linear

1) For a molecule with the formula AB2, the molecular shape is ________. A) linear or bent B) linear or trigonal planar C) linear or T-shaped D) T-shaped E) trigonal planar

A) linear or bent

58) The N-N bond in HNNH consists of ________. A) one σ bond and one π bond B) one σ bond and two π bonds C) two σ bonds and one π bond D) two σ bonds and two π bonds E) one σ bond and no π bonds

A) one σ bond and one π bond

87) The bond order of a homonuclear diatomic molecule can be decreased by ________. A) removing electrons from a bonding MO or adding electrons to an antibonding MO B) adding electrons to a bonding MO or removing electrons from an antibonding MO C) adding electrons to any MO D) removing electrons from any MO E) The bond order of a homonuclear diatomic molecule cannot be decreased by any means.

A) removing electrons from a bonding MO or adding electrons to an antibonding MO

24) A __________ covalent bond between the same two atoms is the longest. A) single B) double C) triple D) They are all the same length. E) strong

A) single

19) The hybridization of the carbon atom in carbon dioxide is ________. A) sp B) sp2 C) sp3 D) sp3d E) sp3d2

A) sp

39) The hybridization scheme for BeF2 is ________. A) sp B) sp2 C) sp3 D) sp3d E) sp3d2

A) sp

60) The hybridization of nitrogen in the H—C=N: molecule is ________. A) sp B) s2p C) s3p D) sp2 E) sp3

A) sp

6) Lattice energy is __________. A) the energy required to convert a mole of ionic solid into its constituent ions in the gas phase B) the energy given off when gaseous ions combine to form one mole of an ionic solid C) the energy required to produce one mole of an ionic compound from its constituent elements in their standard states D) the sum of ionization energies of the components in an ionic solid E) the sum of electron affinities of the components in an ionic solid

A) the energy required to convert a mole of ionic solid into its constituent ions in the gas phase

14) The electron-domain geometry and the molecular geometry of a molecule of the general formula ABn will always be the same if ________. A) there are no lone pairs on the central atom B) there is more than one central atom C) n is greater than four D) n is less than four E) the octet rule is obeyed

A) there are no lone pairs on the central atom

24) Which of the following names is/are correct for the compound ? A) titanium dioxide and titanium (IV) oxide B) titanium (IV) dioxide C) titanium oxide D) titanium oxide and titanium (IV) dioxide E) titanium (II) oxide

A) titanium dioxide and titanium (IV) oxide

5) The molecular geometry of the BrO3- ion is ________. A) trigonal pyramidal B) trigonal planar C) bent D) tetrahedral E) T-shaped

A) trigonal pyramidal

Ca reacts with element X to form an ionic compound with the formula CaX. Al will react with X to form ____

Al2X2

11) Of the following elements, __________ has the most negative electron affinity. A) S B) Cl C) Se D) Br E) I

B

12) ) Sodium is much more apt to exist as a cation than is chlorine. This is because ________. A) chlorine is larger than sodium B) chlorine has a greater ionization energy than sodium does C) chlorine is a gas and sodium is a solid D) chlorine has a greater electron affinity than sodium does E) chlorine is more metallic than sodium

B

7) Of the choices below, which gives the order for first ionization energies? A) Kr > Se > Br > Ga > Ge B) Kr > Br > Se > Ge > Ga C) Ga > Br > Ge > Kr > Se D) Ga > Ge > Se > Br > Kr E) Br > Se > Ga > Kr > Ge

B)

43) In the resonance form of ozone shown below, the formal charge on the central oxygen atom is __________. A) 0 B) +1 C) -1 D) +2 E) -2

B) +1

41) The formal charge on sulfur in SO4^2- is __________, where the Lewis structure of the ion is: A) -2 B) 0 C) +2 D) +4 E) -4

B) 0

42) In the Lewis structure of ClF, the formal charge on Cl is __________ and the formal charge on F is __________. A) -1, -1 B) 0, 0 C) 0, -1 D) +1, -1 E) -1, +1

B) 0, 0

23) The bond length in an HI molecule is 1.61 Å and the measured dipole moment is 0.44 D. What is the magnitude (in units of e) of the negative charge on I in HI? A) 1.6 x 10^-19 B) 0.057 C) 9.1 D) 1 E) 0.22

B) 0.057

36) The Lewis structure of shows __________ nonbonding electron pair(s) on As. A) 0 B) 1 C) 2 D) 3 E) This cannot be determined from the data given.

B) 1

37) The Lewis structure of shows that the central phosphorus atom has __________ nonbonding and __________ bonding electron pairs. A) 2, 2 B) 1, 3 C) 3, 1 D) 1, 2 E) 3, 3

B) 1, 3

8) The central atom in the O3 molecule has ________ nonbonded electron pair(s) and ________ bonded electron pair(s) in its valence shell. A) 6, 2 B) 1, 3 C) 2, 2 D) 3, 1 E) 3, 2

B) 1, 3

71) Based on molecular orbital theory, the bond order of the H—H bond in the H2+ ion is ________. A) 0 B) 1/2 C) 1 D) 3/2 E) 2

B) 1/2

11) The Cl-Si-Cl bond angle in the SiCl2F2 molecule is approximately ________. A) 90° B) 109.5° C) 120° D) 180° E) 60°

B) 109.5°

14) The F-N-F bond angle in the NF3 molecule is slightly less than ________. A) 90° B) 109.5° C) 120° D) 180° E) 60°

B) 109.5°

1) ClF3 has "T-shaped" geometry. There is/are ________ non-bonding domain(s) in this molecule. A) 4 B) 2 C) 3 D) 1 E) 0

B) 2

26) A double bond consists of __________ pairs of electrons shared between two atoms. A) 1 B) 2 C) 3 D) 4 E) 6

B) 2

30) The combination of two atomic orbitals results in the formation of ________ molecular orbitals. A) 1 B) 2 C) 3 D) 4 E) 0

B) 2

45) How many equivalent resonance forms can be drawn for without expanding octet on the sulfur atom (sulfur is the central atom)? A) 0 B) 2 C) 3 D) 4 E) 1

B) 2

72) An antibonding π orbital contains a maximum of ________ electrons. A) 1 B) 2 C) 4 D) 6 E) 8

B) 2

10) The central Xe atom in the XeF4 molecule has ________ unbonded electron pair(s) and ________ bonded electron pair(s) in its valence shell. A) 1, 4 B) 2, 4 C) 4, 0 D) 4, 1 E) 4, 2

B) 2, 4

33) The sp2 atomic hybrid orbital set accommodates ________ electron domains. A) 2 B) 3 C) 4 D) 5 E) 6

B) 3

23) How many single covalent bonds must a silicon atom form to have a complete octet in its valence shell? A) 3 B) 4 C) 1 D) 2 E) 0

B) 4

28) In the Lewis symbol for a sulfur atom, there are __________ paired and __________ unpaired electrons. A) 2, 2 B) 4, 2 C) 2, 4 D) 0, 6 E) 5, 1

B) 4, 2

1) Which ion below has a noble gas electron configuration? A) Li 2+ B) Be2+ C) B2+ D) C2- E) N2-

B) Be2+

46) A valid Lewis structure of __________ cannot be drawn without violating the octet rule. A) NF3 B) BeH2 C) SO2 D) CF4 E) SO3 ^2-

B) BeH2

16) Of the atoms below, __________ is the most electronegative. A) Si B) Cl C) Rb D) Ca E) S

B) Cl

17) Which one of the following species has the electron configuration [Ar] 3d^4? A) Mn2+ B) Cr2+ C) V^3+ D) Fe3+ E) K+

B) Cr2+

17) Which one of the following species has the electron configuration [Ar]3d^4 ? A) Mn 2+ B) Cr^2+ C) V^3+ D) Fe^3+ E) K+

B) Cr^2+

29) In the molecule below, which atom has the largest partial negative charge __________? A) Cl B) F C) Br D) I E) C

B) F

14) In which of the molecules below is the carbon-carbon distance the shortest? A) H2C=CH2 B) H--C=C--H C) H3C--CH3 D) H2C=C=CH2 E) H3C=CH2=CH3

B) H--C=C--H

38) A valid Lewis structure of __________ cannot be drawn without violating the octet rule. A) NF3 B) IF3 C) PF3 D) SbF3 E) So4^2-

B) IF3

38) The Lewis structure of HCN (H bonded to C) shows that __________ has __________ nonbonding electron pairs. A) C, 1 B) N, 1 C) H, 1 D) N, 2 E) C, 2

B) N, 1

52) Which of the following molecules or ions will exhibit delocalized bonding? NO2- NH4+ N3- A) NH4+ and N3- B) NO2- only C) NO2-, NH4+, and N3- D) N3- only E) NO2- and N3-

B) NO2- only

21) Which of the following has the bonds correctly arranged in order of increasing polarity? A) Be--F, Mg--F, N --F, O--F B) O --F, N--F, Be--F, Mg--F C) O--F, Be--F, Mg--F, N--F D) N--F, Be--F, Mg--F, O--F E) M--gF, Be--F, N--F, O--F

B) O --F, N--F, Be--F, Mg--F

20) Of the bonds below, __________ is the least polar. A) Na, S B) P, S C) C, F D) Si, Cl E) Na, Cl

B) P, S

4) Based on the octet rule, phosphorus most likely forms a __________ ion. A) P3+ B) P3- C) P5+ D) P5- E) P+

B) P3-

21) Three monosulfur fluorides are observed: SF2, SF4, and SF6. Of these, ________ is/are polar. A) SF2 only B) SF2 and SF4 only C) SF4 only D) SF6 only E) SF2, SF4, and SF6

B) SF2 and SF4 only

12) Which of the following would have to lose two electrons in order to achieve a noble gas electron configuration? O Sr Na Se Br A) O, Se B) Sr C) Na D) Br E) Sr, O, Se

B) Sr

3) The molecular geometry of ________ is square planar. A) CCl4 B) XeF4 C) PH3 D) XeF2 E) ICl3

B) XeF4

31) Of the following, the central atom is sp3d2 hybridized only in ________. A) PCl5 B) XeF4 C) PH3 D) Br3- E) BeF2

B) XeF4

18) What is the electron configuration for the ion? A) [Ar] 4s^1 3d^6 B) [Ar] 4s^0 3d^7 C) [Ar] 4s^0 3d^5 D) [Ar] 4s^2 3d^9 E) [Ne] 3s^2 3p^10

B) [Ar] 4s^0 3d^7

36) In which of the ions do all X-O bonds (X indicates the central atom) have the same length? A) none B) all C) (i) and (ii) D) (iii) and (v) E) (iii), (iv), and (v)

B) all

53) In order to exhibit delocalized π bonding, a molecule must have ________. A) at least two π bonds B) at least two resonance structures C) at least three σ bonds D) at least four atoms E) trigonal planar electron domain geometry

B) at least two resonance structures

6) The central atom in a certain molecule has 1 nonbonded electron pairs and 2 bonded electron pairs in its valence shell. The molecular geometry of this molecule is ________. A) tetrahedral B) bent C) seesaw D) trigonal bipyrimidal E) trigonal pyramidal

B) bent

8) The molecular geometry of the SF2 molecule is ________. A) linear B) bent C) trigonal planar D) tetrahedral E) octahedral

B) bent

21) Elements from opposite sides of the periodic table tend to form __________. A) covalent compounds B) ionic compounds C) compounds that are gaseous at room temperature D) homonuclear diatomic compounds E) covalent compounds that are gaseous at room temperature

B) ionic compounds

17) The hybridization of orbitals on the central atom in a molecule is sp. The electron-domain geometry around this central atom is ________. A) octahedral B) linear C) trigonal planar D) trigonal bipyramidal E) tetrahedral

B) linear

83) According to MO theory, overlap of two p atomic orbitals produces ________. A) two bonding molecular orbitals B) one bonding molecular orbital and one antibonding molecular orbital C) two bonding molecular orbitals and two antibonding molecular orbitals D) two bonding molecular orbitals and one antibonding molecular orbital E) three bonding molecular orbitals and three antibonding molecular orbitals

B) one bonding molecular orbital and one antibonding molecular orbital

22) In order to produce sp3 hybrid orbitals, ________ s atomic orbital(s) and ________ p atomic orbital(s) must be mixed. A) one, two B) one, three C) one, one D) two, two E) two, three

B) one, three

17) For molecules of the general formula ABn, n can be greater than four ________. A) for any element A B) only when A is an element from the third period or below the third period C) only when A is boron or beryllium D) only when A is carbon E) only when A is Xe

B) only when A is an element from the third period or below the third period

65) 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

B) sigma, pi

59) The hybridization of the terminal carbons in the H2C=C=CH2 molecule is ________. A) sp B) sp2 C) sp3 D) sp3d E) sp3d2

B) sp2

35) The hybridizations of iodine in IF3 and IF5 are ________ and ________, respectively. A) sp3, sp3d B) sp3d, sp3d2 C) sp3d, sp3 D) sp3d2, sp3d E) sp3d2, sp3d2

B) sp3d, sp3d2

7) The central atom in a certain molecule has 4 nonbonded electron pairs and 2 bonded electron pairs in its valence shell. The molecular geometry of this molecule is ________. A) seesaw B) square planar C) linear D) trigonal bipyramidal E) T-shaped

B) square planar

5) The molecular geometry of the SiH2Cl2 molecule is ________. A) trigonal planar B) tetrahedral C) trigonal pyramidal D) octahedral E) T-shaped

B) tetrahedral

9) The molecular geometry of the PF4+ ion is ________. A) octahedral B) tetrahedral C) trigonal pyramidal D) trigonal planar E) trigonal bipyramidal

B) tetrahedral

25) Which of the following names is/are correct for the compound ? A) tin (II) chloride and tin (IV) chloride B) tin tetrachloride and tin (IV) chloride C) tin (IV) tetrachloride D) tin chloride E) tin chloride and tin (II) tetrachloride

B) tin tetrachloride and tin (IV) chloride

12) Using the VSEPR model, the electron-domain geometry of the central atom in O3 is ________. A) linear B) trigonal planar C) tetrahedral D) trigonal bipyramidal E) octahedral

B) trigonal planar

17) Using the VSEPR model, the molecular geometry of the central atom in SO3 is ________. A) linear B) trigonal planar C) tetrahedral D) bent E) trigonal pyramidal

B) trigonal planar

15) A molecule has the formula AB3 and the central atom is in a different plane from the surrounding three atoms. Its molecular shape is ________. A) tetrahedral B) trigonal pyramidal C) linear D) T-shaped E) bent

B) trigonal pyramidal

49) In a polyatomic molecule, "localized" bonding electrons are associated with ________. A) one particular atom B) two particular atoms C) all of the atoms in the molecule D) all of the π bonds in the molecule E) two or more σ bonds in the molecule

B) two particular atoms

1) In which set of elements would all members be expected to have very similar chemical properties? A) P, Se, I B) Cl, Br, Na C) Si, As, Te D) Ne, Na, Mg E) Br, I, At

Br, I, At

15) Oxides of most nonmetals combine with base to form __________. A) hydrogen gas D) water B) an acid E) water and a salt C) a base

C

Of the following species, __________ has the largest radius. A) Rb+ B) Sr2+ C) Br- D) Kr E) Ar

C

Which of the following is not true about alkali metals? A) They are low density solids at room temperature. B) They all readily form ions with a +1 charge. C) They all have 2 electrons in their valence shells. D) They are very reactive elements. E) They have the lowest first ionization energies of the elements.

C

(i) PCl3 (ii) CCl4 (iii) TeCl4 (iv) XeF4 (v) SF6 18) For which of the molecules is the molecular geometry (shape) the same as the VSEPR electron domain arrangement (electron domain geometry)? A) (i) and (ii) B) (i) and (iii) C) (ii) and (v) D) (iv) and (v) E) (v) only

C) (ii) and (v)

40) The formal charge on nitrogen in NO3- is __________. A) -1 B) 0 C) +1 D) +2 E) -2

C) +1

32) The oxidation number of phosphorus in PF3 is __________. A) -2 B) +1 C) +3 D) +2 E) -3

C) +3

3) The H-C-H bond angle in the CH4 ion is approximately ________. A) 180 B) 120 C) 109.5 D) 60 E) 90

C) 109.5

10) The F-B-F bond angle in the BF2- ion is approximately ________. A) 90° B) 109.5° C) 120° D) 180° E) 60°

C) 120°

12) The F-B-F bond angle in the BF3 molecule is ________. A) 90° B) 109.5° C) 120° D) 180° E) 60°

C) 120°

13) The O-S-O bond angle in SO2 is slightly less than ________. A) 90° B) 109.5° C) 120° D) 180° E) 60°

C) 120°

6) There are __________ unpaired electrons in the Lewis symbol for an oxygen atom. A) 0 B) 1 C) 2 D) 4 E) 3

C) 2

1) There are __________ paired and __________ unpaired electrons in the Lewis symbol for a phosphorus atom. A) 4, 2 B) 2, 4 C) 2, 3 D) 4, 3 E) 0, 3

C) 2, 3

5) The central atom in the ICl4- ion has ________ nonbonded electron pair(s) and ________ bonded electron pair(s) in its valence shell. A) 4, 2 B) 0, 4 C) 2, 4 D) 2, 2 E) 6, 0

C) 2, 4

44) How many equivalent resonance forms can be drawn for - (carbon is the central atom)? A) 1 B) 2 C) 3 D) 4 E) 0

C) 3

34) The ion ICL4- has __________ valence electrons. A) 34 B) 35 C) 36 D) 28 E) 8

C) 36

28) The total number of π bonds in the H—C≡C—C≡C—C≡N molecule is ________. A) 3 B) 4 C) 6 D) 9 E) 12

C) 6

39) Based on the octet rule, boron will most likely form a __________ ion. A) B3- B) B1+ C) B3+ D) B2+ E) B2-

C) B3+

43) The central atom in __________ violates the octet rule. A) NH3 B) SeF2 C) BF3 D) AsF3 E) CF4

C) BF3

42) The central atom in __________ does not violate the octet rule. A) SF6 B) KrF2 C) CF4 D) XeF4 E) ICl4

C) CF4

11) The only noble gas without eight valence electrons is __________. A) Ar B) Ne C) He D) Kr E) All noble gases have eight valence electrons.

C) He

45) A valid Lewis structure of __________ cannot be drawn without violating the octet rule. A) NI3 B) SO2 C) ICL5 D) SiF4 E) CO2

C) ICL5

24) Of the following molecules, only ________ is polar. A) CCl4 B) BCl3 C) NCl3 D) BeCl2 E) Cl2

C) NCl3

37) Of the following, __________ cannot accommodate more than an octet of electrons. A) P B) As C) O D) S E) I

C) O

31) Given the electronegativities below, which covalent single bond is most polar? Element: H C N O Electronegativity: 2.1 2.5 3.0 3.5 A) C-H B) N-H C) O-H D) O-C E) O-N

C) O-H

51) Which of the following molecules or ions will exhibit delocalized bonding? SO2 SO3 SO32- A) SO2, SO3, and SO32- B) SO32- only C) SO2 and SO3 D) SO3 and SO32- E) None of the above will exhibit delocalized bonding.

C) SO2 and SO3

19) Of the molecules below, only ________ is polar. A) CCl4 B) CH4 C) SeF4 D) SiCl4

C) SeF4

11) Fe+2 ions are represented by __________. A) [Ar]3d1 B) [Ar]3d4 C) [Ar]3d6 D) [Ar]3d104s1 E) [Ar]3d3

C) [Ar]3d6

76) Molecular Orbital theory correctly predicts diamagnetism of fluorine gas, F2. This is because ________. A) the bond order in F2 can be shown to be equal to 1. B) there are more electrons in the bonding orbitals than in the antibonding orbitals. C) all electrons in the MO electron configuration of F2 are paired. D) the energy of the π2pMOs is higher than that of the σ2p MO E) the F—F bond enthalpy is very low

C) all electrons in the MO electron configuration of F2 are paired.

2) 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

C) core level electron pair

26) The Lewis structure of N2H2 shows __________. A) a nitrogen-nitrogen triple bond B) a nitrogen-nitrogen single bond C) each nitrogen has one nonbonding electron pair D) each nitrogen has two nonbonding electron pairs E) each hydrogen has one nonbonding electron pair

C) each nitrogen has one nonbonding electron pair

30) The ability of an atom in a molecule to attract electrons is best quantified by the __________. A) paramagnetism B) diamagnetism C) electronegativity D) electron change-to-mass ratio E) first ionization potential

C) electronegativity

32) Electronegativity __________ from left to right within a period and __________ from top to bottom within a group. A) decreases, increases B) increases, increases C) increases, decreases D) stays the same, increases E) increases, stays the same

C) increases, decreases

13) The type of compound that is most likely to contain a covalent bond is __________. A) one that is composed of a metal from the far left of the periodic table and a nonmetal from the far right of the periodic table B) a solid metal C) one that is composed of only nonmetals D) held together by the electrostatic forces between oppositely charged ions E) There is no general rule to predict covalency in bonds.

C) one that is composed of only nonmetals

84) According to MO theory, overlap of two p atomic orbitals produces ________. A) one π MO and one σ* MO B) one π MO and one σ MO C) one π MO and one π* MO or one σ MO and one σ* MO D) one π+ MO and one σ* MO E) two π MOs, two π+ MOs, one σ MO, and one σ* MO

C) one π MO and one π* MO or one σ MO and one σ* MO

33) To convert from one resonance structure to another, __________. A) only atoms can be moved B) electrons and atoms can both be moved C) only electrons can be moved D) neither electrons nor atoms can be moved E) electrons must be added

C) only electrons can be moved

66) Structural changes around a double bond in the ________ portion of the rhodopsin molecule trigger the chemical reactions that result in vision. A) protein B) opsin C) retinal D) cones E) rods

C) retinal

13) The electron-domain geometry and the molecular geometry of a molecule of the general formula ABn are ________. A) never the same B) always the same C) sometimes the same D) not related E) mirror images of one another

C) sometimes the same

55) The carbon-carbon σ bond in ethylene, H2C=CH2, 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

C) sp2 hybrid orbitals

38) The hybrid orbitals used for bonding by Xe in the unstable XeF2 molecule are ________ orbitals. A) sp2 B) sp3 C) sp3d D) sp3d2 E) sp

C) sp3d

13) Using the VSEPR model, the electron-domain geometry of the central atom in ClO3- is ________. A) linear B) trigonal planar C) tetrahedral D) trigonal bipyramidal E) octahedral

C) tetrahedral

6) The molecular geometry of the left-most carbon atom in the molecule below is ________. A) trigonal planar B) trigonal bipyramidal C) tetrahedral D) octahedral E) T-shaped

C) tetrahedral

34) For resonance forms of a molecule or ion, __________. A) one always corresponds to the observed structure B) all the resonance structures are observed in various proportions C) the observed structure is an average of the resonance forms D) the same atoms need not be bonded to each other in all resonance forms E) there cannot be more than two resonance structures for a given species

C) the observed structure is an average of the resonance forms

10) The electron-domain geometry and molecular geometry of iodine trichloride are ________ and ________, respectively. A) trigonal bipyramidal, trigonal planar B) tetrahedral, trigonal pyramidal C) trigonal bipyramidal, T-shaped D) octahedral, trigonal planar E) T-shaped, trigonal planar

C) trigonal bipyramidal, T-shaped

18) The hybridization of orbitals on the central atom in a molecule is sp2. The electron-domain geometry about this central atom is ________. A) octahedral B) linear C) trigonal planar D) trigonal bipyramidal E) tetrahedral

C) trigonal planar

6) The molecular geometry of the PHCl2 molecule is ________. A) bent B) trigonal planar C) trigonal pyramidal D) tetrahedral E) T-shaped

C) trigonal pyramidal

22) The molecular geometry of the PF3 molecule is ________, and this molecule is ________. A) trigonal planar, polar B) trigonal planar, nonpolar C) trigonal pyramidal, polar D) trigonal pyramidal, nonpolar E) tetrahedral, unipolar

C) trigonal pyramidal, polar

45) The highest energy occupied molecular orbital in the C—C bond of the C2 molecule is _____. A) σ2p B) σ*1p C) π2p D) π2s E) π*2p

C) π2p

13) In the generation of most anions, the energy change (kJ/mol) that _______ an electron is ________. A) removes, positive D) adds, negative B) adds, positive E) None of the above is correct C) removes, negative

D

In ionic bond formation, the lattice energy of ions_____ as the magnitude of the ion charges______ and the radii ____ . A) increases, decrease, increase B) increases, increase, increase C) decreases, increase, increase D) increases, increase, decrease E) increases, decrease, decrease

D

Which equation correctly represents the first ionization of aluminum? A) Al- (g) → Al (g) + e- B) Al (g) → Al- (g) + e- C) Al (g) + e- → Al- (g) D) Al (g) → Al+ (g) + e- E) Al+ (g) + e- → Al (g)

D

6) Which isoelectronic series is correctly arranged in order of increasing radius? A) K+ < Ca2+ < Ar < Cl- B) Cl- < Ar < K+ < Ca2+ C) Ca2+ < Ar < K+ < Cl- D) Ca2+ < K+ < Ar < Cl- E) Ca2+ < K+ < Cl- < Ar

D)

(i) PCl3 (ii) CCl4 (iii) TeCl4 (iv) XeF4 (v) SF6 29) In which of the molecules does the central atom utilize d orbitals to form hybrid orbitals? A) (i) and (ii) B) (iii) only C) (i) and (v) D) (iii), (iv), and (v) E) (v) only

D) (iii), (iv), and (v) (iii) TeCl4 (iv) XeF4 (v) SF6

(i) (ii) (iii) (iv) (v) 35) There can be four equivalent best resonance structures of __________. A) (ii) B) (iii) C) (i) D) (iv) E) (v)

D) (iv)

70) Based on molecular orbital theory, the bond orders of the H—H bonds 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

D) 1, 1/2, and 1/2

28) What is the maximum number of double bonds that a carbon atom can form? A) 4 B) 1 C) 0 D) 2 E) 3

D) 2

78) Based on molecular orbital theory, there is/are ________ unpaired electron(s) in the OF+ ion. A) 0 B) 3 C) 1 D) 2 E) 1/2

D) 2

79) Based on molecular orbital theory, the bond order of the N—N bond in the N22+ ion is ________. A) 0 B) 3 C) 1 D) 2 E) 1/2

D) 2

27) There are __________ valence electrons in the Lewis structure of CH3CH2Cl. A) 14 B) 12 C) 18 D) 20 E) 10

D) 20

9) Which energy change corresponds to the first ionization energy of potassium? A) 2 B) 5 C) 4 D) 3 E) 6

D) 3

25) How many hydrogen atoms must bond to silicon to give it an octet of valence electrons? A) 1 B) 2 C) 3 D) 4 E) 5

D) 4

16) PCl5 has ________ electron domains and a ________ molecular arrangement. A) 6, trigonal bipyramidal B) 6, tetrahedral C) 5, square pyramidal D) 5, trigonal bipyramidal E) 6, seesaw

D) 5, trigonal bipyramidal

2) In the Lewis symbol for a fluorine atom, there are __________ paired and __________ unpaired electrons. A) 4, 2 B) 4,1 C) 2, 5 D) 6, 1 E) 0, 5

D) 6, 1

10) The halogens, alkali metals, and alkaline earth metals have __________ valence electrons, respectively. A) 7, 4, and 6 B) 1, 5, and 7 C) 8, 2, and 3 D) 7, 1, and 2 E) 2, 7, and 4

D) 7, 1, and 2

10) The electron configuration [Kr]4d10 represents __________. A) Sr+2 B) Sn+2 C) Te+2 D) Ag+1 E) Rb+1

D) Ag+1

4) Of the following species, ________ will have bond angles of 120°. A) PH3 B) ClF3 C) NCl3 D) BCl3 E) All of these will have bond angles of 120°.

D) BCl3

19) Of the molecules below, the bond in __________ is the most polar. A) HBr B) HI C) HCl D) HF E) H2

D) HF

22) Determining lattice energy from Born-Haber cycle data requires the use of __________. A) the octet rule B) Coulomb's law C) Periodic law D) Hess's law E) Avogadro's number

D) Hess's law

13) Which of the following would have to gain two electrons in order to achieve a noble gas electron configuration? O Sr Na Se Br A) Br B) Sr C) Na D) O, Se E) Sr, O, Se

D) O, Se

77) Based on molecular orbital theory, the only molecule in the list below that has unpaired electrons is ________. A) C2 B) N2 C) F2 D) O2 E) Li2

D) O2

81) Of the following, only ________ appears to gain mass in a magnetic field. A) C2 B) N2 C) F2 D) O2 E) Li2

D) O2

20) The formula of palladium(IV) sulfide is __________. A) Pd2S4 B) PdS4 C) Pd4S D) PdS2 E) Pd2S2

D) PdS2

18) Which of the elements below has the largest electronegativity? A) Si B) Mg C) P D) S E) Na

D) S

41) A valid Lewis structure of __________ cannot be drawn without violating the octet rule. A) PO4^3- B) SiF4 C) CF4 D) SeF4 E) NF3

D) SeF4

23) Of the following molecules, only ________ is polar. A) BeCl2 B) BF3 C) CBr4 D) SiH2Cl2 E) Cl2

D) SiH2Cl2

15) The electron configuration of the S2- ion is __________. A) [Ar]3S23P6 B) [Ar]3S^2 3P^2 C) [Ne]3S^2 3P^2 D) [Ne] 3s^2 3p^6 E) [Kr] 3s^2 2p^-6

D) [Ne] 3s^2 3p^6

53) Of the possible bonds between carbon atoms (single, double, and triple), __________. A) a triple bond is longer than a single bond B) a double bond is stronger than a triple bond C) a single bond is stronger than a triple bond D) a double bond is longer than a triple bond E) a single bond is stronger than a double bond

D) a double bond is longer than a triple bond

11) An electron domain consists of ________. a) a nonbonding pair of electrons b) a single bond c) a multiple bond A) a only B) b only C) c only D) a, b, and c E) b and c

D) a, b, and c

52) As the number of covalent bonds between two atoms increases, the distance between the atoms __________ and the strength of the bond between them __________. A) increases, increases B) decreases, decreases C) increases, decreases D) decreases, increases E) is unpredictable

D) decreases, increases

55) Dynamite consists of nitroglycerine mixed with __________. A) potassium nitrate B) damp KOH C) TNT D) diatomaceous earth or cellulose E) solid carbon

D) diatomaceous earth or cellulose

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 domains 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

D) electron domains in the valence shell of an atom will arrange themselves so as to minimize repulsions

44) When four atomic orbitals are mixed to form hybrid orbitals, how many hybrid orbitals are formed? A) one B) six C) three D) four E) five

D) four

88) The order of MO energies in B2, C2, and N2 (σ2p > π2p), is different from the order in O2, F2, and Ne2 (σ2p > π2p). 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

D) greater 2s-2p interaction in B2, C2, and N2

7) In ionic bond formation, the lattice energy of ions ________ as the magnitude of the ion charges _______ and the radii __________. A) increases, decrease, increase B) increases, increase, increase C) decreases, increase, increase D) increases, increase, decrease E) increases, decrease, decrease

D) increases, increase, decrease

85) 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

D) is always higher in energy than

57) A typical double bond consists of ________. A) three sigma bonds B) three pi bonds C) one sigma and two pi bonds D) one sigma and one pi bond E) three ionic bonds

D) one sigma and one pi bond

68) In comparing the same two atoms bonded together, the ________ the bond order, the ________ the bond length, and the ________ the bond energy. A) greater, shorter, greater B) greater, greater, greater C) greater, longer, greater D) smaller, longer, smaller E) smaller, greater, greater

D) smaller, longer, smaller

61) The hybridization of carbon in the H—C=N: molecule is ________. A) sp2 B) s2p C) s3p D) sp E) sp3

D) sp

45) A triatomic molecule cannot be linear if the hybridization of the central atoms is ________. A) sp B) sp2 C) sp3 D) sp2 or sp3 E) sp2d or sp3d2

D) sp2 or sp3

34) The hybridizations of nitrogen in NF3 and NH3 are ________ and ________, respectively. A) sp2, sp2 B) sp, sp3 C) sp3, sp D) sp3, sp3 E) sp2, sp3

D) sp3, sp3

16) The electron-domain geometry of a sulfur-centered compound is trigonal bipyramidal. The hybridization of the central sulfur atom is ________. A) sp B) sp2 C) sp3 D) sp3d E) sp3d2

D) sp3d

37) The hybrid orbitals used for bonding by the sulfur atom in the SF4 molecule are ________ orbitals. A) sp B) sp2 C) sp3 D) sp3d E) sp3d2

D) sp3d

41) The electron-domain geometry of the AsF5 molecule is trigonal bipyramidal. The hybrid orbitals used by the As atom for bonding are ________ orbitals. A) sp2d2 B) sp3 C) sp3d2 D) sp3d E) sp2

D) sp3d

21) The electron-domain geometry of the AsF6- ion is octahedral. The hybrid orbitals used by the As atom for bonding are ________ orbitals. A) sp2d2 B) sp3 C) sp3d D) sp3d2 E) sp2

D) sp3d2

42) ________ hybrid orbitals are used for bonding by Xe in the XeF4 molecule. A) sp2 B) sp3 C) sp3d D) sp3d2 E) sp

D) sp3d2

36) The hybridizations of bromine in BrF5 and of arsenic in AsF5 are ________ and ________, respectively. A) sp3, sp3d B) sp3d, sp3d2 C) sp3d, sp3 D) sp3d2, sp3d E) sp3d2, sp3d2

D) sp3d2, sp3d

7) The molecular geometry of the CHCl3 molecule is ________. A) bent B) trigonal planar C) trigonal pyramidal D) tetrahedral E) T-shaped

D) tetrahedral

26) 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

D) tetrahedral, polar

75) Molecular Orbital theory correctly predicts paramagnetism of oxygen gas, O2. This is because ________. A) the bond order in O2 can be shown to be equal to 2. B) there are more electrons in the bonding orbitals than in the antibonding orbitals. C) the energy of the π2p MOs is higher than that of the σ2p MO D) there are two unpaired electrons in the MO electron configuration of O2 E) the O—O bond distance is relatively short

D) there are two unpaired electrons in the MO electron configuration of O2

14) Using the VSEPR model, the electron-domain geometry of the central atom in ClF3 is ________. A) linear B) trigonal planar C) tetrahedral D) trigonal bipyramidal E) octahedral

D) trigonal bipyramidal

11) The electron-domain geometry and molecular geometry of the nitrite ion are ________ and ________, respectively. A) trigonal bipyramidal, trigonal planar B) tetrahedral, trigonal pyramidal C) trigonal bipyramidal,T-shaped D) trigonal planar, bent E) T-shaped, trigonal planar

D) trigonal planar, bent

27) The molecular geometry of the BCl3 molecule is ________, and this molecule is ________. A) trigonal pyramidal, polar B) trigonal pyramidal, nonpolar C) trigonal planar, polar D) trigonal planar, nonpolar E) trigonal bipyramidal, polar

D) trigonal planar, nonpolar

2) The electron domain and molecular geometry of SO3 are ________. A) trigonal bipyramidal, trigonal planar B) trigonal planar, bent C) trigonal bipyramidal, T-shaped D) trigonal planar, trigonal planar E) octahedral, seesaw

D) trigonal planar, trigonal planar

15) The molecular geometry of the H3O+ ion is ________. A) linear B) tetrahedral C) bent D) trigonal pyramidal E) octahedral

D) trigonal pyramidal

51) Of the bonds , and , the bond is __________. A) strongest/shortest B) strongest/longest C) weakest/shortest D) weakest/longest E) intermediate in both strength and length

D) weakest/longest

44) The highest energy occupied molecular orbital in the F—F bond of the F2 molecule is _____. A) π*2s B) π2s C) σ*1p D) π*2p E) π2p

D) π*2p

Atomic radius generally increases as we move

Down a group and from right to left across a period

35) The ion NO- has __________ valence electrons. A) 15 B) 14 C) 16 D) 10 E) 12

E) 12

50) There are ________ σ bonds and ________ π bonds in H3C-CH2-CH CH-CH2-C CH. A) 14, 2 B) 10, 3 C) 12, 2 D) 13, 2 E) 16, 3

E) 16, 3

46) How many equivalent resonance structures can be drawn for the molecule of SO3 without having to violate the octet rule on the sulfur atom? A) 5 B) 2 C) 1 D) 4 E) 3

E) 3

26) There are ________ σ and ________ π bond(s) in the H2C=CH2 molecule. A) 3 and 2 B) 3 and 4 C) 4 and 3 D) 2 and 3 E) 5 and 1

E) 5 and 1

32) The sp3d2 atomic hybrid orbital set accommodates ________ electron domains. A) 2 B) 3 C) 4 D) 5 E) 6

E) 6

27) There are ________ σ and ________ π bonds in the H2C=C=CH2 molecule. A) 4, 2 B) 6, 4 C) 2, 2 D) 2, 6 E) 6, 2

E) 6, 2

47) A typical double bond ________. A) is stronger and shorter than a single bond B) consists of one σ bond and one π bond C) imparts rigidity to a molecule D) consists of two shared electron pairs E) All of the above answers are correct.

E) All of the above answers are correct.

48) Which atom can accommodate an octet of electrons, but doesn't necessarily have to accommodate an octet? A) N B) C C) H D) O E) B

E) B

82) Of the following, ________ appear(s) to gain mass in a magnetic field. B2 N2 O2 A) O2 only B) N2 only C) B2 and N2 D) N2 and O2 E) B2 and O2

E) B2 and O2

2) Of the ions below, only __________ has a noble gas electron configuration. A) S3+ B) O2+ C) I+ D) K+ E) Cl-

E) Cl-

15) Of the atoms below, __________ is the most electronegative. A) Br B) O C) Cl D) N E) F

E) F

5) Based on the octet rule, iodine most likely forms an __________ ion. A) I 2+ B) I 4+ C) I 4- D) I + E) I --

E) I --

40) Which of the following does not have eight valence electrons? A) Cl- B) Xe C) Ti+4 D) Rb+1 E) Sr+1

E) Sr+1

9) The electron configuration of the phosphide ion ( P^3-) is __________. A) [Ne]3s^2 B) [Ne]3s^23p^1 C) [Ne]3s^2 3p^3 D) [Ne]3p^2 E) [Ne]3s^2 3p^6

E) [Ne]3s^2 3p^6

3) Which of the following has eight valence electrons? A) Ti4+ B) Kr C) Cl- D) Na+ E) all of the above

E) all of the above

56) Dynamite __________. A) was invented by Alfred Nobel B) is made of nitroglycerine and an absorbent such as diatomaceous earth C) is a much safer explosive than pure nitroglycerine D) is an explosive E) all of the above

E) all of the above

3) The electron-domain geometry of ________ is tetrahedral. A) CBr4 B) PH3 C) CCl2Br2 D) XeF4 E) all of the above except XeF4

E) all of the above except XeF4

12) The molecular geometry consists of ________. a) a nonbonding pair of electrons b) a single bond c) a multiple bond A) a only B) b only C) c only D) a, b, and c E) b and c

E) b and c

9) According to VSEPR theory, if there are three electron domains in the valence shell of an atom, they will be arranged in a(n) ________ geometry. A) tetrahedral B) octahedral C) linear D) square planar E) bent

E) bent

54) Most explosives are compounds that decompose rapidly to produce __________ products and a great deal of __________. A) gaseous, gases B) liquid, heat C) soluble, heat D) solid, gas E) gaseous, heat

E) gaseous, heat

33) A nonpolar bond will form between two __________ atoms of __________ electronegativity. A) different, opposite B) identical, different C) different, different D) similar, different E) identical, equal

E) identical, equal

15) Using the VSEPR model, the electron-domain geometry of the central atom in XeF4 is ________. A) linear B) trigonal planar C) tetrahedral D) trigonal bipyramidal E) octahedral

E) octahedral

73) According to MO theory, overlap of two s atomic orbitals produces ________. A) one bonding molecular orbital and one hybrid orbital B) two bonding molecular orbitals C) two bonding molecular orbitals and two antibonding molecular orbitals D) two bonding molecular orbitals and one antibonding molecular orbital E) one bonding molecular orbital and one antibonding molecular orbital

E) one bonding molecular orbital and one antibonding molecular orbital

56) The π bond in ethylene, H2C=CH2, results from the overlap of ________. A) sp3 hybrid orbitals B) s atomic orbitals C) sp hybrid orbitals D) sp2 hybrid orbitals E) p atomic orbitals

E) p atomic orbitals

31) Resonance structures differ by __________. A) number and placement of electrons B) number of electrons only C) placement of atoms only D) number of atoms only E) placement of electrons only

E) placement of electrons only

20) The hybridization of the central atom in the XeF4 molecule is ________. A) sp B) sp2 C) sp3 D) sp3d E) sp3d2

E) sp3d2

86) 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

E) the lower will be the energy of the resulting bonding MO and the higher will be the energy of the resulting antibonding MO

2) For a molecule with the formula AB3, the molecular shape is ________. A) linear, octahedral, or bent B) linear, bent, or trigonal planar C) linear, bent, or T-shaped D) tetrahedral E) trigonal planar, trigonal pyramidal, or T-shaped

E) trigonal planar, trigonal pyramidal, or T-shaped

Consider the general valence electron configuration of ns2np5 and the following statements: (i) Elements with this electron configuration are expected to form -1 anions. (ii) Elements with this electron configuration are expected to have large positive electron affinities. (iii) Elements with this electron configuration are nonmetals. (iv) Elements with this electron configuration form acidic oxides.

I II IV

The ion with the largest diameter is Br- Cl- I- F- O(2)-

I-

Of the following, which gives the correct order for atomic radius for Ca, K, As, Ge and Kr? A) Ca > K > As > Ge > Kr B) Kr > Ge > As > K > Ca C) Ge > As > Kr > K > Ca D) K > Ca > Ge > As > Kr E) Kr > As > Ge > Ca > K

K,CA,Ge,As,Kr

Screening the nuclear charge by core electrons in atoms is

More efficient than that by valence electrons

Which noble gas has the lowest first ionization energy?

Radon

OF the following elements, ________ has the most negative electron affinity' O K B Na S

S

3) The atomic radius of main-group elements generally increases down a group because __________. A) effective nuclear charge increases down a group B) effective nuclear charge decreases down a group C) effective nuclear charge zigzags down a group D) the principal quantum number of the valence orbitals increases E) none of the above

The Principle Quantum number of the Valence orbitals increase

Lattice energy is ________

The energy required to convert a mole of ionic solid into its constituent ions in the gas phase

Ozone is a(n) ________ of oxygen

allotrope

Oxides of most nonmetals combine with water to form __________.

an acid

Electrons in the 1s subshell are much closer to the nucleus in Ar than in He due to the larger __________ in Ar. A) nuclear charge B) paramagnetism C) diamagnetism D) Hund's rule E) azimuthal quantum number

nuclear charge