Chapter 1: 1.4 Valence Bond Theory

Question 1

True or False:

Valence bond theory isn’t a real thing

Answer 1

True, it is a mathematical model

Question 2

What is Valence Bond Theory?

Answer 2

A mathematical model that allows us to explain molecular geometry of atoms and lone pairs around acentral atom while considering the orbitals present

Question 3

Using methane as an example:

What is the issue when we consider orbitals and electron configuration?

Answer 3

There are only two unpaired electrons to make bonds

Question 4

How do we fix the issue presented in the methane scenario?

Answer 4

The s-orbital and p-orbitals “hybridize” to form a sigma bond (single bond)

Question 5

What does having “degenerate” energy mean?

Answer 5

Same

Question 6

How is a double bond formed in ethene?

Answer 6

Each carbon makes three sigma bonds and one pi bond

Question 7

What does a pi bond require?

Answer 7

An unhybridized p orbital

Question 8

What do the rest of the orbitals in ethene do?

(Besides the unhybridized p orbital)

Answer 8

Hybridize to make sigma bonds

Question 9

What do pi bonds require?

Answer 9

Unhybridized p-orbitals

Question 10

What do sigma bonds and lone pairs require?

Answer 10

s/p hybrid orbitals

Question 11

List:

Bonds according to bond strength

Answer 11

Triple bonds > Double bonds > Single bonds

Question 12

List:

Bonds according to bond length

Answer 12

Triple bonds < Double bonds < Single bonds

Question 13

What is the relationship for bond length and bond strength?

Answer 13

Inversely proportional to each other