Intermolecular bonding

Question 1

metallic bonding

Answer 1

delocalised electrons
electrostatic attraction
positive metal cores

Question 2

characters of metals

Answer 2

mostly very strong but depends on 
- number of electrons 
-packing of cation
good conductors of heat and electricity in solid and liquid state 
malleable and ductile 
lustrous

Question 3

intramolecular forces

Answer 3

hold atoms together within a molecule

Question 4

intermolecular forces

Answer 4

attractive forces between molecules

- intermolecular forces are much weaker than intramolecular forces

Question 5

four types of intermolecular forces

Answer 5

• ion-dipole
• hydrogen bonds
• dipole-dipole forces
• dispersion forces, Van der Waals forces/London forces

Question 6

London dispersion forces

Answer 6

dipole induces another in the neighbouring atoms/molecules attraction between these dipoles is a weak intermolecular force
strength increases with number of electrons (size) in a molecule

Question 7

dipole-dipole forces

Answer 7

relate to permanent molecular dipoles
- found in bonds with electronegativity difference
- molecular dipoles require a non-uniform charge distribution in 3-D
act in addition to London forces
results in higher boiling points than expected

Question 8

Ion-dipole forces

Answer 8

electrostatics interaction between an ion and an uncharged polar molecule
strength depends on charge on ion and magnitude of the dipole

Question 9

hydrogen bonding

Answer 9

requires an electronegative atom O, N or F delta negative (acceptor)
a S+ hydrogen atom (donor) in a polar bond usually N-H, O-H or F-H

Question 10

bonding in cellulose

Answer 10

major component of cell walls

• polymer of glucose
• sugar chains held rigidly together by multiple Hydrogen bonds within and between chains.
• flat sheets of hydrogen-bonded chains are held together by London dispersion forces.