Module 2: Non-Covalent Interaction Flashcards
Water
most abundant substance in living systems, making up >70% of the weight
high MP, BP, heat of vaporization
2 dipoles
Covalent bond
strong bond, require a lot of energy to break, very stable
Non-covalent bonds
weak bond, not a lot of energy required to break
Bond dissociation energy
energy required to break a bond
for H bond in liquid water=23 kJ/mol
Hydrogen bond donor
atom which H atom bonded to
O, N
Hydrogen bond acceptor
atom w non-bonded e- pair (lone pair)
Hydrophilic
water loving
any compound that readily dissolves in water
polar/charged
Hydrophobic
water hating
any non-polar compound that does not dissolve well in water
Coulombs law states…
like-charges repel while opposite charges attract
closer 2 charges are, stronger the force b/w them
however, very weak force b/w 2 like-charges as they are repelled
***Larger the distance, smaller the force
Repulsive forces
+ + =positive force
- - =positive force
Attractive forces/No force
- =negative force
- /+ 0 =no force
Permittivity
material property that expresses the force between two point charges in the material
Relative permittivity
factor by which the electric field between the charges is decreased relative to a vacuum
Non polar compounds w water
interfere w H bonding of water molecules and do not form new solute-water interactions
Hydrophobic compounds w water
constrains orientation of water molecules
decrease entropy
