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)
Molecular formula
A formula that shows the numbers and kinds of atoms in one molecule of a compound
Structural formula
A molecular representation that show the connections among atoms by using lines to represent covalent bonds.
Lewis structure
A molecular representations that show both the connections among atoms and the locations of lone-pair valence electrons.
Lone pair
A pair of electrons that is not used forbonding
Ionic compounds (general composition)
metal with non-metal
Molecular compounds (general composition)
non-metal with non-metal
