chemistry ch 4-5 (lewis - hybridization)

exception(s) to octect rule: Be

only holds 4 ve (2 bonds)

exception(s) to octect rule: B + Al

can hold 6 ve or a full octect (8 ve)

• doesn’t have to form a full octet if not enough ve

exception(s) to octect rule: S + Xe

can hold up to 12 ve

exception(s) to octect rule: P

can hold up to 10 electrons

exception(s) to octect rule: Cl

holds up to 14 ve

fill dat ho out

4567, 4321, 0123

formal charge of an atom formula

# ve - # bonds to atom - # lone pair electrons

overall charge is equal to

the sum of formal charges

shape when 2 groups around central atom
no lone pairs

linear

shape when 3 groups around central atom

• no lone pairs

trigonal planar

shape when 4 groups around central atom

• no lone pairs

tetrahedral

shape when 5 groups around central atom

• no lone pairs

trigonal bipyramidal

shape when 6 groups around central atom

• no lone pairs

octahedral

shape when 3 groups around central atom

• 1 group is lone pair

bent

shape when 4 groups around central atom

• 1 group is lone pair

trigonal pyramidal

shape when 4 groups around central atom

• 2 groups are lone pairs

bent

shape when 5 groups around central atom

• 1 group is lone pair

see-saw

shape when 5 groups around central atom

• 2 groups are lone pairs

T-shape

shape when 5 groups around central atom

• 3 groups are lone pairs

linear

polarity of a molecule is determined by

electronegativity of atoms + symmetrical shape

# of sigma and pi bonds for each type of bond:
single, double, triple

single = 1 sigma
double = 1 sigma + 1 pi
triple = 1 sigma + 2 pi

hybridization for when groups around the central atom = 5, 4, 3, 2, 1

sp3d, sp3, sp2, sp, s

what is dih

atomic orbitals

what is dih

antibonding

• has the star

• more energy than atomic orbital

what is dih

bonding

• no star

• lower energy than atomic orbital

paramagnetic

unpaired e^- present

diamagnetic

no unpaired e^-

bond order formula

(#e in bonding - #e in anti) / 2

when bond order is greater than 1

stable

• if =0 then unstable

bond order can also determine (other than stability)

number of bonds between two atoms