1. 2.6 Hydrogen Bonding 2.6.1. Hydrogen Bonds
LO: I understand what is meant by hydrogen bonding.

2. Increasing strength of bonds/forces
The bonding in hydrogen fluoride is much stronger than can be accounted for by attractions alone.
polar-polar
This is bonding.
hydrogen
Increasing strength of bonds/forces
van der Waals
ionic
hydrogen
polar-polar
covalent
LO: I understand what is meant by hydrogen bonding.

3. Hydrogen bonds form in molecules where a hydrogen atom is bonded to a , or . atom.
nitrogen
oxygen
fluorine H F + - H O + -
H2O, CH3OH (methanol) H N + -
NH3, CH3NH2 (methylamine)
Hydrogen bonds form between a atom in one molecule and a nitrogen, oxygen or fluorine atom in a neighbouring molecule.
hydrogen
LO: I understand what is meant by hydrogen bonding.

4. Boiling Points
LO: I understand the pattern in the boiling points of the group 7 hydrides.

5. Boiling points of the group 7 hydrides vs period number.HF
HCl
HBr HI
Boiling Point
(˚C)
Period number
Extrapolating the graph from HCl downwards would give a boiling point of ˚C for HF.
-100
Hydrogen
bonding has increased the boiling point of HF by over 100˚C.
LO: I understand the pattern in the boiling points of the group 7 hydrides.

6. H-Bonds and Viscosity
LO: I understand the affect H-bonds have on viscosity.
LO: I understand the affect H-bonds have on viscosity.

7. propan-2-ol propanone H-bonds present H-bonds not present
Propan-2-ol is viscous than propanone due to the H-bonds between the molecules.
more
The H-bonds between the propan-2-ol molecules prevent them from each other easily.
slipping past
LO: I understand the affect H-bonds have on viscosity.