chemical bonding MCQs

 

CHAPTER 5

CHEMICAL BONDING

Q. 1. Which of the following compounds has maximum ionic character?

a. NaCI

b. CsF

c. KBr

d. MgCI2

(b)

 

Q. 2. Which of the following molecules or ions is nonplanar, i.e., has at least one atom that is not

in the same plane as the others?

a. BH3

b. NF3

c. SO3

d. CO3

 (b)

 

Q.3. Which of the following best describes the shape and polarity of the carbon disulfide, CS2, molecule?

a. bent and polar

b. linear and non-polar

c. pyramidal and polar

d. bent and non-polar

(b)

 

Q. 4. Which of the following molecules has the smallest angle between adjacent bonds?

a. CO2

b. CH4

c. H2O

d. NH3

(c)

 

Q.5. The shape of hydronium ion H3O+ is:

a. planar

b. see-saw

c. trigonal planar

d. trigonal pyramidal

(d)

 

Q. 6. Which of the following pairs of atoms are least likely to form an ionic compound?

a. Ni, O

b. Na, F

c. Cu, CI

d. Li, Mg

(d)

 

Q. 7. Which of the following pairs of atoms are most likely to form a covalent compound?

a. Na, F

b. Cu, CI

c. C, O

d. Li, F

(c)

 

Q. 8. Which molecule has one pair of nonbonding electrons on the central atom?

a. PCI3

b. CO2

c. SO3

d. BF3

(a)

 

Q. 9. Which of the following will have the largest dipole moment?

a. HF

b. HCI

c. HBr

d. F2

(a)

 

Q. 10. CO2 is a nonpolar molecular (μ=0) whereas SO2 is polar (μ=1.62D). This difference is due to the fact that:

a. CO2 has an even number of double bonds whereas SO2 has an odd number of

double bonds

b. C and O are in different groups whereas S and O are in the same group

c. The C-O bond is nonpolar while the S-O bond is polar

d. CO2 is linear whereas SO2 is not linear

(d)

 

Q. 11. What is the state of hybridization of the carbon atoms in ethylene, C2H2?

a. sp2

b. sp

c. sp3

d. sp3d2

(a)

 

Q. 12. The type(s) of bonding present in a sample of sodium nitrated, NaNO3, are:

a. covalent bonds only

b. ionic bonds only

c. covalent and ionic bonds

d. ionic and metallic bonds

(c)

 

Q. 13. The C=C double bond in ethane C2H4, is consist of:

a. two П bonds

b. covalent bonds

c. two sigma bonds

d. one П bond + one sigma bond

(d)

 

Q. 14. All of the following statements are false except

a. The number of MO’s in a molecule equals twice the number of constituent atomic

orbitals

b. As bonding MO’s become equally less stable

c. In MO’s, the number of bonding electrons equals the number of antibonding

electrons

d. Each bonding MO can accommodate only one electron

(b)

 

Q. 15. All of the following statements are false except

a. The MO’s in a molecule equals twice the number of constituent atomic orbitals.

b. As bonding MO’s become more stable, antibonding MO’s become equally less

stable.

c. In MO’s, the number of bonding electrons equals the number of antibonding

electrons.

d. Each bonding MO can accommodate only one electron.

(b)

Q. 16. What is the hybridization of phosphorus in PCI3?

a. sp2

b. sp3

c. sp

d. sp3d2

(b)

 

Q. 17. Analysis of an unknown substance showed that it has a high boiling point and is brittle. It is an insulator as a solid but conducts electricity when melted. Which of the following substances would have those characteristics?

a. HCI

b. AI

c. KBr

d. SiF4

(c)

 

Q. 18. Arrange the following bonds in order of increasing bond strength.

C-F, C-Br, C-I, C-CI

a. C-F < C-CI < C-Br < C-I

b. C-I < C-Br < C-CI < C-F

c. C-Br < C-I < C-CI < C-F

d. C-I < C-Br < C-F < C-CI

(b)

 

Q. 19. Based on electronegativity trends in the periodic table, predict which of the following compounds will have the greatest % ionic character in its bonds.

a. H2O

b. LiI

c. RbF

d. HCI

(c)

 

Q. 20. According to VSEPR theory, a molecule with the general formula AX3 will have a _____ molecular shape.

a. linear

b. bent

c. trigonal planar

d. tetrahedral

(c)

 

Q. 21. According to VSEPR theory, a molecule with the general formula AX3E will have a ____ molecular shape.

a. bent

b. trigonal planar

c. trigonal pyramidal

d. tetrahedral

(c)

 

Q. 22. Predict the ideal bond angles around carbon in C2I2 using the molecular shape given by the

VSEPR theory.

a. 90o

b. 109o

c. 120 o

d. 180o

(d)

Q. 23. Predict the actual bond angles in BrF3 using the VSEPR theory.

a. more than 120o

b. between 109o and 120o

c. between 90o and 109o

d. less than 90o

(d)

 

Q. 24. Which of the following has no net dipole moment?

a. N2O

b. NF3

c. H2Se

d. TeO3

(d)

 

Q. 25. A molecule with the formula AX2 uses ………. To form its bonds.

a. sp hybrid orbitals

b. sp2 hybrid orbitals

c. sp3 hybrid orbitals

d. sp3d hybrid orbitals

(a)

 

Q. 26. Valence bond theory predicts that carbon will use -------- hybrid orbitals in the carbonate

anion, CO3

2-

a. sp

b. sp2

c. sp3

d. sp3d

(b)

 

Q. 27. Valence bond theory predicts that sulfur will use -------- hybrid orbitals in sulfur dioxide, SO2.

a. sp

b. sp2

c. sp3

d. sp3d

(b)

 

Q. 28. Which one of the following statements about orbital hybridization is incorrect?

a. The carbon atom is CO2 is sp hybridized

b. The nitrogen atom in NH3 is sp3 hybridized.

c. sp2 hybrid orbitals are coplanar, and at 120o to each other.

d. sp hybrid orbitals lie at 180o to each other.

(b)

 

Q. 29. For which one of the following molecules is the indicated type of hybridization not

appropriate for the central atom?

a. BeCI2 sp2

b. SiH4 sp3

c. BF3 sp2

d. C2H2 sp

(a)

 

Q. 30. According to molecular orbital (MO) theory, the twelve outermost electrons in the O2 molecule are distributed as follows:

a. 12 in bonding MOS, O in antibonding MOs.

b. 10 in bonding MOs, 2 in antibonding MOs.

c. 9 in bonding MOs, 3 in antibonding MOs.

d. 8 in bonding MOs, 4 in antibonding MOs.

(d)

 

Q. 31. According to molecular orbital theory, what is the bond order in the O2

+ ion?

a. 5.5

b. 5

c. 4

d. 2.5

(d)

 

Q. 32. Which of the following statements relating to molecular orbital (MO) theory is incorrect?

a. A bonding MO is lower in energy than the two atomic orbitals from which it is formed.

b. Combination of two 2p orbitals may result in either Л MOs.

c. A species with a bond order of zero will be stable

d. In a stable molecule having an even number of electrons, all electrons must be

paired.

(d)

 

Q. 33. One can safely assume that the 3s- and sp- orbitals will form molecular orbitals similar to those formed when 2s- and sp-orbitals interact. According to molecular orbital theory, what will be the bond order for the CI2 + ion?

a. 0.5

b. 1

c. 1.5

d. 2

(c)