Ch 8 & 9 bonding MC – Flashcards

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.

Atoms having greatly differing electronegativities are expected to form: A) no bonds B) polar covalent bonds C) nonpolar covalent bonds D) ionic bonds E) covalent bonds

Choose the compound with the most ionic bond. A) LiCl B) KF C) NaCl D) LiF E) KCl

Atoms with very similar electronegativity values are expected to form A) no bonds. B) covalent bonds. C) triple bonds. D) ionic bonds. E) none of these

Which of the following bonds is least polar? A) C-O B) H-C C) S-Cl D) Br-Br E) They are all nonpolar.

For the elements Rb, F, and O, the order of increasing electronegativity is: A) Rb < F < O B) Rb < O < F C) O < F < Rb D) F < Rb < O E) None of these

For the elements Cs, F, and Cl, the order of increasing electronegativity is: A) F < Cl < Cs B) Cs < Cl < F C) Cl < Cs < F D) F < Cs < Cl E) None of these

In the gaseous phase, which of the following diatomic molecules would be the most polar? A) CsF B) CsCl C) NaCl D) NaF E) LiF

Based on electronegativities, which of the following would you expect to be most ionic? A) N2 B) CaF2 C) CO2 D) CH4 E) CF4

10. In which case is the bond polarity incorrect? A) δ+H-F δ - B) δ +K-O δ - C) δ +Mg-H δ - D) δ +Cl-I δ - E) δ +Si-S δ -

Which of the following groups contains no ionic compounds? A) HCN, NO2, Ca(NO3)2 B) PCl5, LiBr, Zn(OH)2 C) KOH, CCl4, SF4 D) NaH, CaF2, NaNH2 E) CH2O, H2S, NH3

In which pair do both compounds exhibit predominantly ionic bonding? A) PCl5 and HF B) Na2SO3 and BH3 C) KI and O3 D) NaF and H2O E) RbCl and CaO

Metals typically have _______ electronegativity values. A) high B) low C) negative D) no E) two of these

The electron pair in a C-F bond could be considered A) closer to C because carbon has a larger radius and thus exerts greater control over the shared electron pair. B) closer to F because fluorine has a higher electronegativity than carbon. C) closer to C because carbon has a lower electronegativity than fluorine. D) an inadequate model since the bond is ionic. E) centrally located directly between the C and F.

Based on electronegativity differences, which of the following is most likely to be ionic? A) BaF2 B) Cl2 C) NH3 D) NO3 E) CH4

What is the correct order of the following bonds in terms of decreasing polarity? A) N-Cl, P-Cl, As-Cl B) P-Cl, N-Cl, As-Cl C) As-Cl, N-Cl, P-Cl D) P-Cl, As-Cl, N-Cl E) As-Cl, P-Cl, N-Cl

Which of the following bonds would be the most polar without being considered ionic? A) Mg-O B) C-O C) O-O D) Si-O E) N-O

Which of the following bonds would be the least polar yet still be considered polar covalent? A) Mg-O B) C-O C) O-O D) Si-O E) N-O

How many of the following molecules possess dipole moments? BH3, CH4, PCl5, H2O, HF, H2 A) 1 B) 2 C) 3 D) 4 E) 5

Which of the following molecules has a dipole moment? A) CH4 B) CCl4 C) CO2 D) SO3 E) none of these

Select the molecule among the following that has a dipole moment. A) CO2 B) SeO3 C) XeF4 D) SF4 E) BeCl2

Which of the following molecules (or ions) has a dipole moment? A) CO2 B) CO3 2- C) NH4 + D) PF3 E) two of them do

Which of the following molecules has a dipole moment? A) BCl3 B) SiCl4 C) PCl3 D) Cl2 E) none of these

Which of the following molecules has no dipole moment? A) CO2 B) NH3 C) H2O D) all E) none

Choose the statement that best describes the PbCl4 molecule in the gas phase. A) The bond angles are all about 109°. B) The molecule is polar. C) The molecule has a dipole moment. D) The bonds are nonpolar. E) a, b, and c

Which of the following has a zero dipole moment? A) NH3 B) NO2 C) PF5 D) SO2 E) HCN

Which of the following has the smallest radius? A) Cl- B) K+ C) Cr D) Al3+ E) Ar

Consider the following: I. Al, Si, P, S II. Be, Mg, Ca, Sr III. I, Br, Cl, F IV. Na+, Mg2+, Al3+, Si4+ Which of these is an isoelectronic series? A) IV B) III C) II D) I E) none of them

Which of the following has the smallest ionic radius? A) Ca2+ B) Cl- C) Li+ D) O2- E) Be2+

Which of the following ionic compounds has the largest lattice energy, i.e., the lattice energy most favorable to a stable lattice? A) CsI B) LiI C) LiF D) CsF E) MgO

Calculate the lattice energy for LiF(s) given the following: sublimation energy for Li(s) +166 kJ/mol Delta(Hf) for F(g) +77 kJ/mol first ionization energy of Li(g) +520. kJ/mol electron affinity of F(g) -328 kJ/mol enthalpy of formation of LiF(s) -617 kJ/mol A) 285 kJ/mol B) -650. kJ/mol C) 800. kJ/mol D) -1047 kJ/mol E) None of these

When electrons in a molecule are not found between a pair of atoms but move throughout the molecule, this is called A) ionic bonding. B) covalent bonding. C) polar covalent bonding. D) delocalization of the electrons.

Which of the following statements concerning lattice energy is false? A) It is often defined as the energy released when an ionic solid forms from its ions. B) MgO has a larger lattice energy than NaF. C) The lattice energy for a solid with 2+ and 2- ions should be two times that for a solid with 1+ and 1- ions. D) MgO has a larger lattice energy than LiF. E) All of these are true.

Which of the following pairs is isoelectronic? A) Li+ and K+ B) Na+ and Ne C) I- and Cl- D) S2- and Ne E) Al3+ and B3+

Which of the following arrangements is in order of increasing size? A) Ga3+ > Ca2+ > K+ > Cl- > S2- B) S2- > Cl- > K+ > Ca2+ > Ga3+ C) Ga3+ > S2- > Ca2+ > Cl- > K+ D) Ga3+ > Ca2+ > S2- > Cl- > K+ E) Ga3+ > Ca2+ > S2- > K+ > Cl-

Which of the following types of molecules has a dipole moment (when polar bonds are present)? A) linear molecules with two identical bonds B) tetrahedral molecules (four identical bonds equally spaced) C) trigonal pyramid molecules (three identical bonds) D) trigonal planar molecules (three identical bonds equally spaced) E) None has a dipole moment.

Given the following information: Li(s) ® Li(g) heat of sublimation of Li(s) = 166 kJ/mol HCl(g) ® H(g) + Cl(g) bond energy of HCl = 427 kJ/mol Li(g) ® Li+(g) + e- ionization energy of Li(g) = 520. kJ/mol Cl(g) + e- ® Cl-(g) electron affinity of Cl(g) = -349 kJ/mol Li+(g) + Cl-(g) ® LiCl(s) lattice energy LiCl(s) = -829 kJ/mol H2(g) ® 2H(g) bond energy of H2 = 432 kJ/mol calculate the net change in energy for the reaction 2Li(s) + 2HCl(g) ® 2LiCl(s) + H2(g) A) 363 kJ B) -562 kJ C) -179 kJ D) -73 kJ E) None of these

39. Choose the molecule with the strongest bond. A) F2 B) Cl2 C) Br2 D) I2

44. Using the following bond energies Bond Bond Energy (kJ/mol) CºC 839 C-H 413 O=O 495 C=O 799 O-H 467 estimate the heat of combustion for one mole of acetylene: C2H2(g) + (5/2)O2(g) ® 2CO2(g) + H2O(g)

Which of the following species would be expected to have the highest ionization energy? A) Br- B) Kr C) Se2- D) Sr2+ E) Rb+

As indicated by Lewis structures, which of the following would probably not exist as a stable molecule? A) CH3OH B) CH2O C) CH3O D) C2H2 E) C3H4

Which of the following molecules is non-polar overall? A) SF4 B) SF2 C) CCl4 D) H2S E) OCl2

The hybridization of the phosphorus atom in the cation PH2+ is:

In the molecule C2H4 the valence orbitals of the carbon atoms are assumed to be A) not hybridized. B) sp hybridized. C) sp2 hybridized. D) sp3 hybridized. E) dsp hybridized.

Atoms which are sp2 hybridized form ____ pi bond(s).

The hybridization of the central atom in XeCl3+ is:

The hybridization of the central atom in KrF4O is: