Packet #2 Flashcards
Electronegativity
tendency of an atom to pull shared electrons toward itself when that atom is sharing eledctrons with another atom.
Electronegativity scale
measured on scale of 0-4. Zero is least electronegative and 4 is most electronegative (F is a 4.0)
Electronegativity difference = covalent bond
Difference in electronegativity between the two atoms is 0.5 or greater. (Then it equals a polar covalent bond)
Dispersion forces
weak attrractive forces that are at play in ALL covalent molecules both polar and non-polar. Also called London forces
Dipole forces
attractive forces that result from the partial positive and partial negative charges that form on atoms in polar molecules. Dipole forces are ONLY at play in polar molecules
Hydrogen bonding
this is an extremely stron form of dipole force. Hydrogen bonding is ONLY at play in molecules which contain -N-H, -O-H, or -F-H.
of covalent bonds: H
1
of covalent bonds: C
4
of covalent bonds: O
2
of covalent bonds: F
1
of covalent bonds: Si
4
of covalent bonds: P
3
of covalent bonds: Cl
1
of covalent bonds: S
2
Coordinate covalent bond
The covalent bond that forms when both the electrons are donated by the same atom (Ammonium ion NH4+ is an example)
