1 Refresher and Basics of Organic Chemistry

Question 1

what do S and P orbitals look like

Answer 1

S = spheres
P = dumbells

Question 2

what are the orbitals and how many electrons do they hold

Answer 2

s = 2
p = 6
d = 10

Question 3

what r valence and core electrons and orbitals

Answer 3

V e = electrons found in valence orbitals
V o = occupied orbitals of highest energy of the most outer shell
Core e = lectrons found in core orbitals (NOT available for bonding / as lone pairs)
Core o = fully occupied orbitals of lowest energy

Question 4

what are sigma bonds

Answer 4

direct (head-on) overlap between two orbitals.

Question 5

what is constructive overlap

Answer 5

orbital overlaps with 1 other orbital (2 sigmas)

Question 6

what is deconstructive overlap

Answer 6

2 orbitals of different phases overlap (anti bonding interaction)

Question 7

what are pi bonds

Answer 7

indirect (side-on) overlap between two orbitals (the two orbitals are not able to directly overlap, instead simply coming closer together and slightly ‘bending’ to constructively overlap)

Question 8

TF all pi bonds are formed by 2 P orbitals

Answer 8

T

Question 9

which delta EN value means its polar, non polar, or ionic

Answer 9

NP = <0.4
P = 0.4<1.5
Ionic = >1.5

Question 10

what is electronegativity

Answer 10

how much atoms want electrons

Question 11

how do we determine if a bond is polar

Answer 11

the difference in EN between atoms
○ 4.0-2.5 = 1.5 —> polar

Question 12

TF sigma bonds are more easily broken then pi bonds

Answer 12

False, Pi bonds are more easily broken

Question 13

what is repulsion in VSEPR theory

Answer 13

maximizing distance between outer electrons

Question 14

what are the bond angles of a compound with… 2 groups, 3 groups, 4 groups

Answer 14

• 2 groups = linear (180 degrees apart)
  ○ 3 = trigonal planar (120 degrees apart)
  ○ 4 = tetrahedral (109 degrees apart)

Question 15

TF The better the overlap between orbitals the better the bond

Answer 15

T

Question 16

if there is 2 groups connected to a carbon its is an ___ carbon

Answer 16

sp

Question 17

if there is 3 groups connected to a carbon its is an ___ carbon

Answer 17

sp2

Question 18

if there is 4 groups connected to a carbon its is an ___ carbon

Answer 18

sp3

Question 19

TF
○ Atoms (usually a C) with single bonds are sp
○ Any atom with a double bond has to have and sp2
- Any atoms within a triple bond has to have and sp3

Answer 19

False
○ Atoms with single bonds are sp3
○ Atoms with double bonds are sp2
- Atoms with triple bonds are sp

Question 20

how do we calculate formal charge

Answer 20

FC = (# valence elecrons) - (# of bonds) - (# non-bonded electrons)