unit 3

Question 1

According to the VSEPR model, a molecule with the general formula AB5 with one lone pair on the central atom will have a ________ molecular geometry.

Answer 1

square pyramidal

Question 2

What is the predicted molecular geometry of the IBr3 molecule according to the VSEPR model?

Answer 2

T-shaped

Question 3

Which of the following pure substances has the highest boiling point?
-CH4
-CCl4
-CI4
-CF4
-CBr4

Answer 3

CI4

Question 4

According to the VSEPR model, what is the predicted electron-domain geometry around the central iodine atom in the ion lF2– ?

Answer 4

trigonal bipyramidal

Question 5

The number of π bonds in phosgene, COCl2, is

Answer 5

1

Question 6

Which one of the following molecules is polar?
-CO2
-F2
-CH4
-CBr4
-CHBr3

Answer 6

CHBr3

Question 7

What is the formal charge on the fluorine in ClF2+?

Answer 7

0

Question 8

Ammonia’s unusually high melting point is the result of

Answer 8

hydrogen bonding.

Question 9

Which of the following contains ionic bonding?
-SrF2
-OCl2
-Al
-HCl
-CO

Answer 9

SrF2

Question 10

Carbon uses ________ hybrid orbitals in ClCN.

Answer 10

sp

Question 11

A molecule with the formula AB4 and a square planar molecular geometry uses ________ to form its σ bonds.

Answer 11

sp3d2 hybrid orbitals

Question 12

What is the intermolecular force that exists between a calcium ion and water?

Answer 12

ion-dipole forces

Question 13

Which of these elements is most likely to exhibit an expanded octet in its compounds?
-Na
-C
-O
-S
-N

Answer 13

S

Question 14

According to the VSEPR model, which molecule is predicted to be linear?
-H2S
-BF3
-HCN
-H2CO
-SO3

Answer 14

HCN

Question 15

Select the strongest bond in the following group.

-C–C
-C–O
-C–F
-C≡C
-C=C

Answer 15

C≡C

Question 16

At a temperature of 27 K, neon condenses due to

Answer 16

London dispersion forces.

Question 17

A polar covalent bond would form in which one of these pairs of atoms?
-Si – Si
-Cl – Cl
-P – Cl
-Cr – Br
-Ca – Cl

Answer 17

P – Cl

Question 18

What is the hybridization of As in the AsF4– ion?

Answer 18

sp3d

Question 19

What is the total number of electron domains around the central atom for a molecule having a square planar molecular geometry, such as XeBr4?

Answer 19

6

Question 20

A nonpolar covalent (i.e., pure covalent) bond would form….
-Br – Br
-Na – Cl
-H – Cl
-Se – Br
-Li – Br

Answer 20

Br – Br

Question 21

Which is the most reasonable prediction for the three F–Br–F bond angles in BrF3?

Answer 21

86°, 86°, and 172°

Question 22

The percent ionic character of a bond ________ electronegativity of the bonding atoms ________.

Answer 22

increases as the difference in; increases

Question 23

Consider the species N2–, N2, and N2+. Which of these species will be paramagnetic?

Answer 23

N2+ and N2–

Question 24

What is the molecular geometry of NOCl as predicted by the VSEPR model?

Answer 24

bent

Question 25

The number of resonance structures for the sulfur dioxide molecule that satisfy the octet rule is

Answer 25

2