Intermolecular Forces

Question 1

What are the 3 types of intermolecular forces??

Answer 1

1. Van Der Waals
2. Dipole-dipole
3. Hydrogen bonding

Question 2

Order the bonding types from weakest to strongest…

Answer 2

1. Van Der Waals (weakest)
2. Dipole dipole
3. Hydrogen bonding (strongest)

Question 3

Van Der Waals act between…

Answer 3

…all molecules/atoms

Question 4

Dipole-dipole and Hydrogen bonding act between…

Answer 4

…certain types of molecules

Question 5

Van Der Waals occur when…

Answer 5

There are more electrons at one end of the atom, just through chance.

Question 6

More electrons at one end of the atom results in…

Answer 6

…the formation of a very slight negative charge at one end of the atom (delta negative)

Question 7

The side which has less electrons results in…

Answer 7

…a slight positive charge (delta positive)

Question 8

When there are more electrons on one end of the atom - when there’s a delta negative and delta positive - it is called…

Answer 8

An instantaneous dipole

Question 9

Can an instantaneous dipole cause another instantaneous dipole in another atom?

Answer 9

Yes

Question 10

What attractive force is formed between two dipoles??

Answer 10

Van Der Waals

Question 11

As the size of the atom increases, the boiling point…

Answer 11

…increases because the atom is larger, so there is a larger force of attraction

Question 12

Instantaneous dipoles can happen in any substance in which atoms can…

Answer 12

…move around. (So it is unlikely in solids)

Question 13

As the boiling point increases the atomic number…

Answer 13

…increases

Question 14

As boiling point increases the number of electrons…

Answer 14

…increases because the atom is larger.

Question 15

The arrangement of polar bonds can result in a molecule becoming…

Answer 15

…polar overall

Question 16

If a molecule is polar overall, we say the molecule has a…

Answer 16

…dipole moment.

Question 17

Dipoles on different molecules can interact. This causes an…

Answer 17

…attractive force between different molecules.

Question 18

Dipole forces are (1.)… in a molecule. This makes dipole-dipole forces (2.)… than Van Der Waals.

Answer 18

(1. )… Permanent

(2. )… Stronger

Question 19

What causes ‘delta -‘ in van Der Waals?

Answer 19

The random movement of electrons.

Question 20

What causes the ‘delta -‘ in dipole dipole molecules?

Answer 20

Electronegativity

Question 21

When finding the boiling point, what three things do you have to consider?

Answer 21

1. Intramolecular forces
2. Intermolecular forces
3. Atom size

Question 22

What three bonds are ‘intermolecular’?

Answer 22

1. Ionic
2. Covalent
3. Metallic

Question 23

What three bonds are ‘intermolecular’?

Answer 23

1. Van Der Waals
2. Dipole-dipole
3. Hydrogen bonding

Question 24

Define a ‘Hydride’:

Answer 24

A compound in which an element is bound with hydrogen

Question 25

Define intermolecular forces:

Answer 25

Forces that exist between molecules