Isomerism

Question 1

What is the definition of isomerism?
What is the definition of structural isomerism?
What is the definition of stereoisomerism?

Answer 1

Compounds with a same molecular formula different arrangement of atoms in space

Compounds with the same molecule formula but a different structural formula

Compounds with a same molecular and structural formula but different arrangement of atoms/bonds in space

Question 2

Structural isomers

What are the 3 ways and definitions of them?

Answer 2

Chain isomerism
Two or more ways of arranging the carbon skeleton of a molecule

Positional isomerism
Same carbon skeleton but functional group attached to different places on the chain

Functional group isomerism
Same molecular formula,different functional group

Question 3

Stereo isomerism

What are the 2 forms?

Answer 3

Optical and E-Z

Question 4

E-Z isomerism
 Also known as?(2)
 Why does it occur?
 When is it not possible?
 What does it cause differences in?(2)
 What is the optimum of different groups that can be attached?

Answer 4

Geometric or cis-trans
Because of restricted movement around the C=C
When groups around the carbon are the same
Physical properties such as bpt and not
Intermolecular force strengths
4

Question 5

Optical isomerism
When does it occur?
What are they known as?
What is chilarity the lack of?
What is the chiral/asymmetric carbon?
How do you test for optical isomers?
Does it effect physical properties?
What are chemical properties? Except with?

Answer 5

When there is a carbon attached to 4 other groups
Optical isomers/enantiomers
Plane line of symmetry
Carbon linked to four different atoms/groups
Plane polarised light will be roasted equally in opposite directions
No they are similar
Similar except with other optically inactive substances

Question 6

What is the difference between normal light and plan polarised light?

Answer 6

Normal light has waves vibrating in all planes plane polarised is in one plane

Question 7

What is an equimolar mixture?
What else is it known as?
Does it rotate plane polarised light? Why?

Answer 7

Mixture with 50/50 of the enantiomers
Racemic mixture or racemate
No because it is optically inactive

Question 8

What are 2 optical isomers?

Answer 8

Non super imposable

Question 9

What do chiral carbons not have?

What molecules have optical isomers?

Answer 9

Plane of symmetry

Chiral molecules

Question 10

What is an aliphatic compound?

Answer 10

Organic compound without a benzene ring