Simple Molecular and Intermolecular Forces Flashcards
Why is the melting point of C higher than N2, O2, F2 and Ne?
C is a giant covalent lattice
The rest are simple covalent lattices, held together by weak intermolecular forces
What are London Forces?
Movement of electrons causes temporary dipoles which induce dipoles in neighbouring molecules
Which elements have London Forces?
Non-metals from group 5-8/0
Why does melting and boiling point increase as you go down group 7?
There are more electrons, so London forces are stronger so more energy is needed to break the intermolecular forces
What is a hydrogen bond?
Strongest intermolecular force
Requires a very electronegative atom with a lone pair (N, O, F)
Requires a very d+ H
a form of dative covalent bond
Why is ice less dense than water?
It forms an open lattice structure due to hydrogen bonding between the molecules
Why does ice have a high melting and boiling point?
It takes a lot energy to break the strong hydrogen bonds between the water molecules throughout
Why does ice have a high surface tension?
It takes a lot energy to break the strong hydrogen bonds at the liquid surface
