Major Ideas: Intermolecular Bonding

Question 0

Name the 3 types of van der Waals forces.

Answer 0

• dipole-dipole
• dispersion
• hydrogen bonding

Question 1

What are intermolecular forces collectively known as?

Answer 1

Van der Waals forces

Question 2

How do you predict molecular shape?

Answer 2

Using “valence shell electron pair repulsion theory”

- valence electron pairs in an Atom repel on another and are positioned as far apart as possible

Question 3

Name the 5 molecular shapes

Answer 3

• Linear
• bent/V-shaped
• trigonal planar
• pyramidal
• tetrahedral

Question 4

What is a polar covalent bond?

Answer 4

Bond in which there is a difference in electonegativity of the atoms involved in the bond, causing electrons to be attracted closer to the more electronegative atom

Question 5

What must a molecule have in order to be classified as polar?

Answer 5

At least ONE polar covalent bond

Question 6

What does it mean when a molecule is a dipole?

Answer 6

Centres of positive and negative charges are at different points in the molecule

Question 7

Between what do dispersion forces exist and how do trey result?

Answer 7

Between all molecules, atoms and ions

- result from the attraction between instantaneous or induced dipoles

Question 8

How do you increase dispersion forces’ strength?

- 2 ways

Answer 8

• Increase the number of electrons

- greater fiat surface area

Question 9

Between what are dipole-dipole forces present?

Answer 9

Polar molecules

Question 10

When do H-bonds take place?

Answer 10

Between polar molecules containing an N-H, O-H or F-H bond and the other N,O or F

Question 11

Hydrogen bonds are _____ ________ than other van der Waals forces but about _______ of the strength of a covalent bond

Answer 11

• 10x
• stronger
• one tenth