Intermolecular forces Flashcards
What are the types of molecules that are held together by instantaneous dipole forces?
Every molecule.
What are Instantaneous dipole forces?
They are forces which occur in every molecule.
Why do Instantaneous dipole forces get stronger as the molecular size increases?
As the molecular size increases there are therefore more electrons and charges on the molecule will have the ability to be stronger.
How are non-polar and/or un-charged molecules attracted to one another?
These molecules have charge just as polar and charged molecules do. Therefore their electrons can be distributed unevenly and form Instantaneous dipole forces.
Are polar or non-polar molecules held together by Permanent Dipole Forces?
Polar molecules
What is the difference between Instantaneous dipole forces and Permanent Dipole forces?
Instantaneous Dipole forces occur in every molecule by partial charges. Permanent Dipole can only occur between polar molecules as it requires permanent charged regions.
What atoms do a molecule need to be able to use hydrogen bonding?
The molecule needs to contain a hydrogen atom attached to either a fluorine, oxygen or nitrogen atom.
How do hydrogen bonds differ from permanent dipole forces?
Hydrogen bonding can only occur within certain special molecules and Permanent dipole forces can only occur between polar molecules.
How are solids converted to liquids and how are liquids converted to gases?
As temperature increases heat energy increases which coverts liquids to solids ect.
What does the melting/boiling points tell us about the molecule?
It tells us the strength of attraction between atoms.
What is the relationship between melting/boiling points & intermolecular forces?
The stronger the intermolecular forces the more heat energy required to to break the bonds. (melting/boiling points)
Which intermolecular forces are the weakest and which are the strongest?
In order
- Instantaneous dipole forces
- Permanent dipole forces
- Hydrogen bonding
What are covalent bonds?
Bonds formed when a pair of electrons are shared between two atoms.
What are Ionic Bonds?
The electrostatic attraction that exists between a positive ion and a negative ion.
