Unit 10- Molec structures and bonding theories

Question 1

VSEPR

Answer 1

predicts shapes from Lewis structures by assuming a molec had a slope that mins electrostatic repulsions between valence shell e- pairs
- min repulsion results when the e- pairs are as far apart as possible

Question 2

steric #

Answer 2

steric = (# of LONE pairs on central atom) + (# of ATOMS bonded to central atom)
- determined from the lewis structure

Question 3

bonded-atom lone-pair arrangement

Answer 3

shape that max the distances between the valence shell e- pairs
- determined by steric #
2: linear
3: trigonal planar
4: terahedral
5: trigonal bipyramidal
6: octahedral

Question 4

molec shapes

Answer 4

the description of the positions of the atoms and not the lone pairs
- derived from the BALP
- when the central atom has NO lone pairs, the molec shape and BALP are IDENTICAL

Question 5

electron pair repulsions

Answer 5

lone pair-lone pair > lone pair-bonding pair > bonding pair-bonding pair
- lone pairs ALWAYS occupy the equatorial positions in a trigonal bipyramid

Question 6

polarity of molec

Answer 6

1) molec shape
2) magnitude and direction of each bond dipole
3) vector sum of bond dipoles
- molec with dipole moment are polar and those without are nonpolar
- same terminal atoms = nonpolar and diff - polar

Question 7

valence bond theory

Answer 7

describes bonds as being formed by overlap of partially filled valence orbitals

Question 8

hybrid orbitals

Answer 8

orbitals obtained by mixing 2 or more atomic orbitals or the same centeral atom

Question 9

steric number: 3
bonded atoms: 2
lone pairs: 1

Answer 9

BALP: trigonal planar
shape: bent

Question 10

steric number: 4
bonded atoms: 3
lone pairs: 1

Answer 10

BALP: tetrahedral
Shape: trigonal pyramidal

Question 11

steric number: 4
bonded atoms: 2
lone pairs: 2

Answer 11

BALP: tetrahedral
Shape: bent

Question 12

steric number: 5
bonded atoms: 4
lone pairs: 1

Answer 12

BALP: trigonal bipyramidal
Shape: see-saw

Question 13

steric number: 5
bonded atoms: 3
lone pairs: 2

Answer 13

BALP: trigonal bipyramidal
Shape: T-shaped

Question 14

steric number: 5
bonded atoms: 2
lone pairs:3

Answer 14

BALP: trigonal bipyramidal
Shape: linear

Question 15

steric number: 6
bonded atoms: 5
lone pairs: 1

Answer 15

BALP: octahedral
Shape: square pyramid

Question 16

steric number: 6
bonded atoms: 4
lone pairs: 2

Answer 16

BALP: octahedral
Shape: square planar

Question 17

hybridization

Answer 17

2: sp
3: sp^2
4: sp^3
5: sp^3d
6: sp^3d^2

Question 18

sigma and pi bonds

Answer 18

single bond: 1 o
double bond: 1o, 1pi
triple bond: 1o, 2pi

Question 19

Isomers

Answer 19

diff cpds with the same molec formula but diff structures

Question 20

molec orbital theory

Answer 20

a model that combines atomic orbitals to from new molec orbitals that are shared over the entire molec

Question 21

bonding molec orbital

Answer 21

concentrates e- density between atoms in a molec

Question 22

antibonding molec orbital

Answer 22

reduces e- density between atoms in a molec
- indicated with *

Question 23

bond order

Answer 23

1/2 [# of e- in bonding orbitals - # of e- in antibonding orbitals]

Question 24

1st period molec orbital diagrams

Answer 24

o1s and o*1s

Question 25

2nd period molec orbital diagrams

Answer 25

o2s, o2s, pi(o2p), o2p, pi(o2p), o*2p

Question 26

e- config of molec orbital diagrams

Answer 26

list of the orbital filled^# of e- in orbital