CHEM 123 FINAL EXAM QUESTIONS AND ACCURATE
ANSWERS A+ GRADED
Hybridization for 2 repelling groups - ANSWER sp
Hybridization for 3 repelling groups - ANSWER sp²
Hybridization for 4 repelling groups - ANSWER sp³
Hybridization for 5 repelling groups - ANSWER sp³d
Hybridization for 6 repelling groups - ANSWER sp³d²
Single bonds - ANSWER - sigma bonds
- rotational symmetry about the internuclear axis
- high amount of overlap
- strong
- electron density in nuclei
Multiple bonds - ANSWER - pi bond
- lower overlap
,- weaker bond
- electron density is above
- much more reactive
Antibonding - ANSWER destructive, destabilizes molecule
Non bonding - ANSWER non interactive
Bonding - ANSWER constructive, stabilizes
MO Bond order - ANSWER 1/2(# bonding e - # antibonding e)
- 0 = not stable
- 1 = single bond
- 2 = double bond
Delocalize MO - ANSWER - compounds described by resonance
- lowest bonding molecular orbital is usually delocalized
Periodic trends - ANSWER -extremes of periodic table are highly reactive, because they are
closer to noble gas configuration
- move from left to right, atoms get smaller, attraction for e increases, usually IE is the same
, (higher)
- atom gets bigger as you go down
Ionics compounds - ANSWER - formed between metal and non metal
Forces between ions - ANSWER - ions with opposite charge
- strong forces for higher charges and smaller ions
Covalent compound - ANSWER - formed between 2 non metals sharing electrons
Lewis structures rules - ANSWER C - 4
H-1
O-2
N-3
Group 7 - 1
1. Draw skeleton
2. Count # of valence electrons including charge
3. Deduct 2 e from each bond
4. Distribute remaining electrons to give all atoms an octet
Bond lengths - ANSWER - Distance between 2 bonded atoms
ANSWERS A+ GRADED
Hybridization for 2 repelling groups - ANSWER sp
Hybridization for 3 repelling groups - ANSWER sp²
Hybridization for 4 repelling groups - ANSWER sp³
Hybridization for 5 repelling groups - ANSWER sp³d
Hybridization for 6 repelling groups - ANSWER sp³d²
Single bonds - ANSWER - sigma bonds
- rotational symmetry about the internuclear axis
- high amount of overlap
- strong
- electron density in nuclei
Multiple bonds - ANSWER - pi bond
- lower overlap
,- weaker bond
- electron density is above
- much more reactive
Antibonding - ANSWER destructive, destabilizes molecule
Non bonding - ANSWER non interactive
Bonding - ANSWER constructive, stabilizes
MO Bond order - ANSWER 1/2(# bonding e - # antibonding e)
- 0 = not stable
- 1 = single bond
- 2 = double bond
Delocalize MO - ANSWER - compounds described by resonance
- lowest bonding molecular orbital is usually delocalized
Periodic trends - ANSWER -extremes of periodic table are highly reactive, because they are
closer to noble gas configuration
- move from left to right, atoms get smaller, attraction for e increases, usually IE is the same
, (higher)
- atom gets bigger as you go down
Ionics compounds - ANSWER - formed between metal and non metal
Forces between ions - ANSWER - ions with opposite charge
- strong forces for higher charges and smaller ions
Covalent compound - ANSWER - formed between 2 non metals sharing electrons
Lewis structures rules - ANSWER C - 4
H-1
O-2
N-3
Group 7 - 1
1. Draw skeleton
2. Count # of valence electrons including charge
3. Deduct 2 e from each bond
4. Distribute remaining electrons to give all atoms an octet
Bond lengths - ANSWER - Distance between 2 bonded atoms
