IB Bonding Flashcards
(IB) COVALENT BONDING
The unpaired electron of each no-metal atom overlap to fill a bonding orbital
(IB) What does each atom have a strong attraction to
it’s own electron and the electron of the neighbouring atom
(IB) BOND LENGTH
The distance between the nuclei of 2 bonded atoms
(IB) PERFECT DISTANCE
minimizes repulsions and maximizes attractions between the 2 atoms
(IB) Factor that affect bond length
Size of atoms
Bond Order
(IB) SIZE OF ATOMS
The valence electrons form the covalent bonds
(IB) pattern for the size of atoms
the bigger the atom, the further the valence electrons from the nucleus, therefore the bond length increases.
(IB) BOND LENGTH
of shared pairs of electron
- single covalent bond = bond order is 1
- double covalent bond = bond order is 2
(IB) bond length pattern
as the bond order inc. the bond length dec.
- inc. #of electrons for the nuclei to be attracted to
- further overlap of bonding orbitals (VBT)
(IB) BOND ENERGY (ENTHALPY)
Bond strength; how strong is the bond?
- how much energy is stored in the bond
(IB) chemical reaction reactants to individual atoms
breaking bonds (requires energy) (endo)
(IB) chemical reactions individual atoms to products
forming new bonds (releases energy) (exo)
- new attractions
(IB) Difference in enthalply
how much energy released v. how much energy required
(IB) EQUATION FOR ENTHALPY
sum of(bond energy enthalpy reactants) - sum of(bond energy enthalpy of bonds forming)
(IB) COORDINATE COVALENT BOND
lone pair becomes a bond pair
(IB) RADICAL
unpaired electron (most)
- unpaired electron occupies the same space as a lone pair
(IB) properties of a RADICAL
- very unstable
- high potential energy
- very reactive
(IB) EXPANDED OCTET
central atom is p3 or higher, since it has available space (d-sublevel) for more than 4 shared pairs of electron
(IB) lone pair =
2 bonding electron
(IB) central atom could have how many bond sites/lone pairs in an expanded octet
5-8
(IB) RESONANCE STRUCTURES
multiple acceptable lewis structures that differ in the location of lone pairs and multiple bonds
(IB) FAVOURED RESONANCE STRUCTURE
(IB) typically, one of the resonance structures is the most likely/favoured structure
(IB) FORMAL CHARGE
(IB) calculation performed in order to determine the most likely/acceptable resonance structure
(IB) formal charge formula
(# of valence electron) - (# of lone pair electron) - 1/2(# of bonding electron)
(IB) what does the best resonance structure have
lowest difference in formal charge
(IB) is high or low magnitude preferred for resonance structure
low magnitude
(IB) what is the tie-breaker for a favoured resonance structure?
the more EN atom should have a more negative FC
(IB) AMMONIUM
NH4^+
(IB) HYDROXIDE
OH^-
(IB) NITRATE
NO3^-
(IB) HYDROGEN CARBONATE (BICARBONATE)
HO3^-
(IB) CARBONATE
CO3^2-
(IB) SULFATE
SO4^2-
(IB) PHOSPHATE
PO4^3-
