Organic Chemistry

Question 1

How are Single Bonds, double bonds and triple bonds drawn in line formula ?

Answer 1

1 line (120’), 2 lines (120’), 3 lines (180’)

Question 3

How would you draw a single, double and triple bond in line formula ?

Answer 3

1 line (120’), 2 line (120’), 3 lines (180’)

Question 4

What do we call a Carbon with more bonds than possible ?

Answer 4

Texas Carbon

Question 5

What is an isomer ?

Answer 5

Multiple compounds that share the same molecular formula, but different structural formula.

Question 6

What is Constitutional Isomers ?

Answer 6

Isomers with the same atoms but different connectivity.

Question 7

What are the two types of isomers ?

Answer 7

Constitutional isomers and Stereoisomers

Question 8

What is the main differences between an alkane and alkenes geometry ?

Answer 8

Alkane has single bonds which can rotate freely, where double bonds (Alkenes) can’t

Question 9

What are the two types of Stereoisomer ?

Answer 9

Diastereomer and Enantiomer

Question 10

What are the two versions of Diastereomers ?

Answer 10

Cis/ trans/ E/Z OR Chiral diastereomers

Question 11

What are Cis and Trans isomers ?

Answer 11

Cis - groups on the same side, Trans - groups on opposite sides

Question 12

How do we differentiate an alkene without H substituent on each end ?

Answer 12

Need to distinguish top/bottom (assign priority

Question 13

How do we assign priority to groups ?

Answer 13

Connectivity (Cahn-Ingold-Prelog Priority). We split into left and right and number each branch in terms of ATOMIC NUMBER

Question 14

What are Z-Alkenes ?

Answer 14

Priority on the SAME side

Question 15

What are E-Alkenes ?

Answer 15

Priority on the OPPOSITE side

Question 16

What is an Enantiomer ?

Answer 16

Non-superimposable mirror images

Question 17

True or False ? The properties of enantiomers have different physical properties, melting, point, density, NMR Spectra

Answer 17

False

Question 18

What does an enantiomer require ?

Answer 18

A stereogenic centre (contains four different groups)

Question 19

What is the turn ?

Answer 19

An arrow drawn from highest priority to lowest priority

Question 20

What is the difference between S and R turns ?

Answer 20

S - Arrow goes anticlockwise(left), R - Arrow goes clockwise(right)

Question 21

What does Non-Superimposable mean ?

Answer 21

They don’t overlay - don’t have an identical layout

Question 22

What are Diastereomers ?

Answer 22

NOT Superimposable, NOT mirror images

Question 23

What are the two methods for the Newman Projection ?

Answer 23

• Sawhorse
• Algorithm

Question 24

(Newman Projection) What is the angle between substituents on adjacent carbons ?

Answer 24

180’ (Dihedral angle)

Question 25

What are the steps in Conformation ?

Answer 25

STAGGERED: (180’) low energy state that puts big subsitients far apart

ECLIPSED: (0’) unstable high energy transition state, drawn differently

GAUCHE (60’) local minimum, less stable than staggered.

Question 26

What is Steric Bulk ?

Answer 26

Thermodynamic penalty for big groups moving close

Question 27

Why are chains a zig-zag ?

Answer 27

Steric Bulk (low energy more straight)

Question 28

TOPIC 5 !!!!!!!!!!!!!