Chapter 25 - Nomenclature and isomerism

Question 1

Give the functional group and naming for alkenes

Answer 1

C=C
* -ene

Question 2

Give the functional group and naming for alkynes

Answer 2

C≡C
* -yne

Question 3

Give the functional group and naming for haloalkanes

Answer 3

X
* Fluoro-
* Chloro-
* Bromo-
* Iodo-

Question 4

Give the functional group and naming for carboxylic acids

Answer 4

• COOH
• -oic acid

Question 5

Give the functional group and naming for anhydrides

Answer 5

O=C-O-C=O
* -anhydride

Question 6

Give the functional group and naming for esters

Answer 6

-COO-
* -oate

Question 7

Give the functional group and naming for acyl chlorides

Answer 7

COCl
* -oyl chloride

Question 8

Give the functional group and naming for amides

Answer 8

CON
* -amide

Question 9

Give the functional group and naming for nitriles

Answer 9

C≡N
* -nitrile

Question 10

Give the functional group and naming for aldehydes

Answer 10

-COH
* - al

Question 11

Give the functional group and naming for ketones

Answer 11

C=O (middle of chain)
* -one

Question 12

Give the functional group and naming for alcohols

Answer 12

OH
* -ol
* hydroxy-

Question 13

Give the functional group and naming for amines

Answer 13

NH2
* -amine
* amino-

Question 14

What makes a molecule chiral?

Answer 14

• A carbon attached to 4 different groups
• This makes it an optical isomer

Question 15

Describe polarised light

Answer 15

• Passed through a polaroid
• All vibrations are cut out except those in one plane

Question 16

Describe how optical isomers can be identified using polarised light

Answer 16

1. Pass the polarised light through a solution of each optical isomer (must be same concentration)
2. (+)-isomer will rotate light clockwise
3. (-)-isomer will rotate light anti-clockwise

Question 17

Define racemic mixture/racemate

Answer 17

• 50:50 mixture of two optical isomers
• Not optically active because the effects of the two isomers cancel out

Question 18

Describe how the drug industry may deal with optical isomerism

Answer 18

• Seperate the isomers - May be difficult and expensive due to similar properties
• Sell as a mixture - Wasteful as half is inactive
• Design alternative synthesis that only produces required isomer