Deck 10: Chemical Bonding I: Basic Concepts

Question 1

Which of the following is least likely to form multiple bonds?

A) phosphorus
B) oxygen
C) nitrogen
D) carbon
E) barium

Answer 1

barium

Question 2

Which chloride should have the greatest covalent character?

A) NaCl
B) BeCl2
C) KCl
D) BaCl2
E) CaCl2

Answer 2

BeCl2

Question 3

In a Lewis structure, a terminal atom is bonded to two or more atoms.

Answer 3

False

Question 4

Choose the INCORRECT statement.

A) The core electrons are called valence electrons.
B) Ionic bonds are formed by the attraction between cations and anions.
C) Ionic bonds are formed from atoms by a transfer of electrons.
D) Covalent bonds are formed by atoms sharing electrons.
E) An octet is 8 outer-shell electrons.

Question 5

Which of the following species contains a triple bond?

A) NH3
B) HCCl3
C) NO3-
D) CO32-
E) CN-

Question 6

In a Lewis structure, usually each atom acquires an outer-shell octet of electrons; H has 2 outer shell electrons.

Question 7

Choose the INCORRECT statement.

A) In a Lewis structure, a covalent bond can be represented by a pair of electrons or a dash.
B) Pairs of electrons not involved in bonding are called lone pairs.
C) A molecule of two atoms is called a diatomic molecule.
D) Two electrons involved in a bond produce a double bond.
E) Three electron pairs involved in a bond produce a triple bond.

Question 8

The central atom is typically the atom with the highest electronegativity.

Question 9

In a Lewis structure, the number of valence electrons shown is one less for each negative charge.

Question 10

Polar bonds are caused by the bonding pair of electrons being attracted more to one atom than the other.

Question 11

A chemical bond for which one of the bonded atoms provides both electrons for the bond is referred to as a:

A) double covalent bond
B) coordinate covalent bond
C) formal covalent bond
D) free radical bond
E) VSEPR bond

Question 12

In which of the following molecules would you expect the nitrogen-to-nitrogen bond to be the shortest?

A) N2H4
B) N2
C) N2O4
D) N2O
E) NH3

Question 13

Choose the INCORRECT statement.

A) A Lewis symbol consists of a chemical symbol and the outer shell electrons.
B) In a Lewis symbol, the chemical symbol represents the nucleus of the atom.
C) A Lewis structure is a combination of Lewis symbols that represent the transfer or sharing of electrons in a chemical bond.
D) An ion written as a Lewis symbol has brackets outside the electrons.
E) An ion written as a Lewis symbol has the charge written as a superscript outside the closing bracket.

Question 14

The core electrons are called valence electrons.

Question 15

Valence electrons are:

A) all electrons of the last rare gas configuration
B) electrons in filled orbits
C) electrons in the shell of the highest principal quantum number
D) unpaired electrons
E) paired electrons

Question 16

A chemical bond for which one of the bonded atoms provides both electrons for the bond is referred to as a coordinate covalent bond

Question 17

Covalent bonds are formed by atoms sharing electrons.

Question 18

Bonds between like atoms are nonpolar bonds.

Question 19

Choose the INCORRECT statement.

A) Bonds between like atoms are nonpolar bonds.
B) Polar bonds are caused by the bonding pair of electrons being attracted more to one atom than the other.
C) Electronegativity is the ability of an atom to attract electrons when involved in a bond.
D) A difference in electronegativity between two atoms causes a polar bond.
E) If the ΔEN value is large the bond is polar covalent.

Question 20

A Lewis structure is a combination of Lewis symbols representing either the transfer or the sharing of electrons in a chemical bond.

Question 21

As indicated by Lewis structures, which of the following molecules would probably be unstable?

A) NH3
B) N2H6
C) SF4
D) CH2F2
E) SiH4

Question 22

After drawing the Lewis dot structure of HC(O)OH, pick the INCORRECT statement from the following.

A) The oxygen not also bonded to hydrogen has a double bond to carbon.
B) The carbon has a lone pair.
C) Both oxygens have two lone pairs.
D) The O-H bond is a single bond.
E) The C-H bond is a single bond.

Question 23

Choose the INCORRECT statement.

A) In a Lewis structure, the number of valence electrons shown is one more for each negative charge.
B) The central atom is typically the atom with the highest electronegativity.
C) One atom supplies both electrons for a coordinate covalent bond.
D) Formal charges are apparent charges associated with atoms in a Lewis structure.
E) Resonance is when more than one plausible structure can be written but the "correct" structure cannot be written.

Question 24

Which of the following species is best represented by a resonance hybrid having two contributing structures?

A) nitric acid
B) nitrous acid
C) nitride ion
D) nitrate ion
E) nitrogen

Question 25

Which of the following is diamagnetic?

A) N2
B) O2-
C) SO2+
D) O2
E) NO2

Question 26

Based on the Lewis structures, which of the following molecules would you expect to exhibit resonance?

A) LiH
B) CH4
C) HNO2
D) OF2
E) none of these

Question 27

Which of the following bonds is probably the most polar?

A) NH in NH3
B) OH in H2O
C) PH in PH3
D) SeH in SeH2
E) CH in CH4

Question 28

After drawing the Lewis dot structure of CH2CCl2, pick the INCORRECT statement of the following.

A) The CC bond is a double bond.
B) The HC bonds are single bonds.
C) The ClC bonds are single bonds.
D) Each carbon has a lone pair.
E) Each chlorine has three lone pairs.

Question 29

Choose the INCORRECT statement.

A) In a Lewis structure, a terminal atom is bonded to two or more atoms.
B) In a Lewis structure all valence electrons must appear.
C) In a Lewis structure, usually all electrons are paired.
D) In a Lewis structure, usually each atom acquires an outer-shell octet of electrons; H has 2 outer shell electrons.
E) In Lewis structures, most multiple covalent bonds are formed by C, N, O, P, and S.

Question 30

After drawing the Lewis dot structure of HOClO2, pick the INCORRECT statement of the following.

A) The oxygen bonded to the hydrogen has two lone pairs.
B) The oxygens not bonded to hydrogen have three lone pairs.
C) The OCl bonds are all double bonds.
D) The HO bond is a single bond.
E) Chlorine has a full octet.

Question 31

Choose the INCORRECT statement.

A) Molecules with all paired electrons are diamagnetic.
B) Highly reactive molecular fragments with unpaired electrons are free radicals.
C) An expanded octet has larger electron clouds.
D) Electron pairs repel each other.
E) VSEPR stands for valence-shell electron pair repulsion.

Question 32

After drawing the Lewis dot structure of HCN, pick the INCORRECT statement from the following.

A) The C-N bond is a double bond.
B) There are no lone pairs on C.
C) The C-H bond is a single bond.
D) There is a lone pair of electrons on N.
E) There are no lone pairs on H.

Question 33

Which of the following exhibits covalent bonding?

A) NaF
B) SrO
C) LiH
D) OF2
E) K2S

Question 34

Which of the following would be properly classified as a set of covalent molecules?

A) NaClO4, C4H10, NH3
B) NaCl, CH4, S8
C) CO2, HCN, O2
D) CO2, NH4Cl, C2H6
E) AgCl, ScF3, P4

Question 35

Which of the following is diamagnetic?

A) ClO2
B) NO
C) CO
D) NO2
E) CH3

Question 36

Which of the following must be paramagnetic?

A) F2
B) N2
C) SO2+
D) H2
E) ClO2-

Question 37

With the representations of "I" for ionic bond, "PC" for polar covalent bond, and "NP" for nonpolar covalent bond, which of the following descriptive combinations is correct?

A) CsF/PC
B) F2/I
C) NO/NP
D) HCl/PC
E) BrCl/NP

Question 38

An expanded octet may occur:

A) in the 1st and 2nd period only
B) in families IA, IIA, and IIIA only
C) anywhere except period 1 and 2
D) in all families except IA
E) in the 3rd and 4th period only

Question 39

Which of the following exhibits ionic bonding?

A) C2H6
B) Na2S
C) H2CO
D) SiCl4
E) SF4

Question 40

Which of the following species exhibits resonance?

A) OF2
B) ClO3-
C) N2
D) PCl5
E) BrF3

Question 41

How many "dots" should be shown in the Lewis symbol for phosphorus?

A) 1
B) 3
C) 5
D) 8
E) 10

Question 42

Write a Lewis structure for BaO.

A)
B)
C)
D) [BaO]
E)

Question 43

Which of the following sets contains only linear molecules?

A) CO2, HCN, O2
B) H2S, HCN, CO2
C) H2O, CO, Cl2
D) H2S, CO, CO2
E) BF3, Cl2, O2

Question 44

Choose the INCORRECT statement.

A) Molecules with unpaired electrons are paramagnetic.
B) The bond order describes whether a covalent bond is single, double or triple.
C) A larger bond order means a shorter bond length.
D) Polar covalent bonds involve equal sharing of electrons in a bond.
E) Bonds between like atoms share electrons equally.

Question 45

Which of the following molecules is polar?

A) NBr3
B) CH4
C) CS2
D) NH4+
E) PCl5

Question 46

Given the bond enthalpies CC (348), CO (707), OO (498), HO (464), CH (414) all in kJ/mol, compute ΔH° kJ/mol for the complete combustion of C7H16.

A) -3.13 × 103 kJ/mol
B) -2.93 × 103 kJ/mol
C) -2.57 × 103 kJ/mol
D) -2.43 × 103 kJ/mol
E) +2.57 × 103 kJ/mol

Question 47

Choose the correct statement about the compound SO2.

A) The S atom has an unshared electron pair.
B) The SO bonds are ionic in character.
C) The two SO bonds have different lengths since one is a single bond and the other a double bond.
D) The molecule has a linear structure.
E) The O atoms have no unshared electron pairs.

Question 48

How many "dots" should be shown for the oxygen symbol in lithium oxide?

A) 2
B) 4
C) 6
D) 8
E) 10

Question 49

Which of the following molecules has both an electron group geometry and a molecular geometry described as trigonal planar?

A) SiH4
B) PF3
C) OF2
D) CHF3
E) BF3

Question 50

Which compound would be expected to have the shortest carbon-carbon bond?

A) H3CCH3
B) HCCH
C) H2CCH2
D) F3CCF3
E) Cl2CCCl2

Question 51

Which of the following has a molecular structure best described as involving an "incomplete octet"?

A) OF2
B) BF3
C) CF4
D) NF3
E) F2

Question 52

Which of the following statements correctly describe the basic concepts and uses of VSEPR theory:
I. The VSEPR theory is used for estimating bond angles.
II. The VSEPR theory is used for predicting electronegativities.
III. The VSEPR theory is helpful in predicting polarity.
IV. The VSEPR theory states that electron pairs repel each other.
V.The VSEPR theory uses valence electron counting for structure prediction.

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

Question 53

Which of the following molecules is nonpolar?

A) HCN
B) CHCl3
C) H2O
D) HClO4
E) BCl3

Question 54

Choose the groups of molecules below in which all the molecules have a net dipole moment.

A) SiHCl3, O2, H2O
B) HF, H2C=CH2, H2O
C) HF, CH3Cl, H2O
D) CCl4, HCl, NH3
E) HF, H2O, N2

Question 55

Which of the following molecules contains polar bonds but has a zero dipole moment?

A) N2
B) NH3
C) CO2
D) CH3Cl
E) BrCl

Question 56

Which compound would be expected to have the shortest nitrogen-nitrogen bond?

A) H2NNH2
B) HNNH
C) N2
D) O2NNO2
E) (CH3)2NNH2

Question 57

Which of the following is a bent (nonlinear) molecule?

A) CO2
B) CS2
C) BeF2
D) OF2
E) XeF2

Question 58

Which of the following has a molecular structure that can be represented without use of an "expanded octet"?

A) Fe(CN)63-
B) C2Cl6
C) SF6
D) PF5
E) PtCl5-

Question 59

Which of the following species has a pyramidal structure?

A) ClO3-
B) ClO4-
C) ClO2-
D) ClO2

Question 60

Choose the INCORRECT statement.

A) The geometrical distribution of electron groups is the electron-group geometry.
B) The geometrical arrangement of the atomic nuclei is the molecular geometry.
C) A polar molecule has a dipole moment.
D) A dipole moment is the product of the number of atoms and the charge.
E) A nonpolar molecule can have polar bonds.

Question 61

After drawing the Lewis dot structure for CH3Cl, determine the number of single bonds, double bonds, and lone pairs on the central atom.

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

Question 62

How many bond pairs ("bp") and how many lone pairs ("lp") should be shown in the Lewis structure for carbon monoxide?

A) 1 bp/4 lp
B) 2 bp/3 lp
C) 3 bp/2 lp
D) 4 bp/1 lp
E) 5 bp/0 lp

Question 63

What is the formal charge on N in NO3-?

A) +2
B) -2
C) +1
D) -1
E) 0

Question 64

After drawing the Lewis dot structure for PCl3, determine the number of single bonds, double bonds, and lone pairs on the central atom.

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

Question 65

What is the formal charge on B in BF4-?

A) +1
B) -1
C) +2
D) 0
E) -2

Question 66

After drawing the Lewis dot structure for XeCl4, determine the number of single bonds, double bonds, and lone pairs on the central atom.

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

Question 67

After drawing the Lewis dot structure for IF7, determine the number of single bonds, double bonds, and lone pairs on the central atom.

A) 3, 2, 1
B) 7, 0, 1
C) 7, 0, 0
D) 1, 0, 0
E) 4, 0, 0

Question 68

Arrange the following in order of increasing electronegativity: Cs, F, As, Cl.

A) As < Cl < Cs < F
B) Cl < As < F < Cs
C) As < F < Cs < Cl
D) Cl < Cs < F < As
E) Cs < As < Cl < F

Question 69

After drawing the Lewis dot structure for BeCl2, determine the number of single bonds, double bonds, and lone pairs on the central atom.

A) 2, 0, 0
B) 2, 0, 2
C) 2, 0,1
D) 0, 2, 0
E) 1, 1, 0

Question 70

Write a Lewis structure for calcium hydride.

A)
B)
C)
D) HCaH
E) CaH

Question 71

After drawing the Lewis dot structure for CO2, determine the number of single bonds, double bonds, and lone pairs on the central atom.

A) 2, 2, 0
B) 2, 0, 2
C) 0, 2, 0
D) 2, 0, 1
E) 0, 2, 2

Question 72

What is the formal charge on P in PCl5?

A) +5
B) +2
C) +1
D) 0
E) -1

Question 73

Write a Lewis structure for barium fluoride.

A)
B) FBF
C)
D)
E)

Question 74

What is the formal charge on carbon in the bicarbonate ion (HOCO2)?

A) +2
B) -2
C) +1
D) -1
E) 0

Question 75

After drawing the Lewis dot structure for XeCl2, determine the number of single bonds, double bonds, and lone pairs on the central atom.

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

Question 76

What is the molecular shape of BrF5?

A) linear
B) square pyramid
C) square planar
D) octahedral
E) trigonal bipyramid

Question 77

Write a Lewis structure for sodium iodide.

A)
B)
C)
D) NaI
E)

Question 78

The electron-pair geometry of H2O is ________.

A) tetrahedral
B) linear
C) trigonal planar
D) bent
E) V-shaped

Question 79

After drawing the Lewis dot structure for CH2O, determine the number of single bonds, double bonds, and lone pairs on the central atom.

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

Question 80

Write a Lewis structure for potassium oxide.

A)
B) KO
C) KOK
D)
E)