chem topic 4B

Question 1

how does bonding occur in VBT

Answer 1

-overlaps between half filled orbitals
-each atom must donate one electron
-overlapping areas have greater electron density

Question 2

What is a sigma bond

Answer 2

an overlap from:
-two s orbitals
-one s and one p orbitals
-two p orbitals (end-to-end)

Question 3

what forms first then second

Answer 3

sigma then pie

Question 4

what is a pi bond

Answer 4

form from side on side overlap of two p orbitals
-single bonds are all sigma
-double bond is one sigma one pi
-triple bonds are one sigma two pi

Question 5

True or False: Hybrid orbitals have unequal energy and from new orbitals

Answer 5

false. they are degenerate and have equal energy because you cant create new orbitals

Question 6

how to hybrid orbitals look? how are hybrid orbitals positioned?

Answer 6

-hybrids have two lobes, like a p orbital
-to minimize repulsion between the large lobes

Question 7

what happens if central atom has lone pairs?

Answer 7

they will be placed in its own hybrid orbitals

Question 8

Do you get rid of the 3rd orbital placement in Sp2? What does it become?

Answer 8

-Three Sp2 hybrid obritals and 1 unhybrid p orb

Question 9

leftover unhybridized orbitals can also make what?

Answer 9

pi bonds

Question 10

H is almost always what orbital

Answer 10

H 1S

Question 11

all other elements in the p side are almost what orbital

Answer 11

ex- O 2P

Question 12

what bonds can/cant rotate

Answer 12

-Can- Sigma (single bond)
-Cant- Pi (double or triple)

Question 13

are sp orbitals linear?

Answer 13

yes

Question 14

Do you get rid of the 2nd and 3rd orbital placement in Sp? What does it become?

Answer 14

• 1 2s and 1 2p with 2 unhybridized p orbitals

Question 15

sp3d and sp3d2 are used for what?why?

Answer 15

-elements that have greater octet
-because they include d orbitals

Question 16

Give the hybridized orbital, orbital combination, and shape for 4 domains

Answer 16

-sp3
-s + 3xp
-tetrahedral

Question 17

Give the hybridized orbital, orbital combination, and shape for 5 domains

Answer 17

-sp3d
-s+ 3xp + d
-trigonal bipyramidal

Question 18

Give the hybridized orbital, orbital combination, and shape for 2 domains

Answer 18

-sp
-s + p
-linear

Question 19

Give the hybridized orbital, orbital combination, and shape for 6 domains

Answer 19

-sp3d2
s+ 3xp + 2xd
-octahedral

Question 20

Give the hybridized orbital, orbital combination, and shape for 3 domains

Answer 20

-sp2
-s+ 2xp
-trigonal planar

Question 21

overlapping p orbitals create what network?

Answer 21

delocalized

Question 22

paramagnetism

Answer 22

oxygen having unpaired electrons

Question 23

what is molecular orbital theory

Answer 23

-quantum chemistry view of molecules and most accurately describes their electronic structure
-generated from a linear combination of atomic orbitals (con and des waves)

Question 24

constructive and destructive form what

Answer 24

C: bonding
D: antibonding

Question 25

rules for drawing MO

Answer 25

-# of MO formed=# of orbitals -orb combined most effectively with other orb of similar energy -effectiveness of orb combination is proportional to their overlap (as overlap increases, bonding MO energy decreses and anti bonding MO decreases) -"mooooo"

Question 26

Bond order and its formula

Answer 26

-describes the strength and number of bonds between two atoms -larger=stronger -0 bond= no bond -non integer are possbile -Bond order= 1/2 (# of bonding e- # of anti bonding e)

Question 27

draw the MO diagrams, what elements belong to which

Answer 27

pi 2 p first: B2 C2 N2 sigma 2 p first: O2 F2 Ne2