Isomerism

Isomers

Have the same molecular formula but different arrangements of carbon atoms

Properties of isomers

Have the same chemical properties but different physical properties

Structural isomers

Compounds with the same molecular formula but different structural formula

Stereoisomers

Compounds with the same structural formula but with different arrangements in space

E Z isomerism

Is an example of stereoisomerism arising from restricted rotation about a double bond, 2 different groups must be attached to each carbon atom of the CdoublebondC group

Cis trans isomerism

Are a special case of EZ isomerism in which two of the subsituent groups are the same

Types of structural isomerism

Chain, positional, functional group

What is chain isomerism caused by

Different arrangements of carbon skeleton

How do the properties of chain isomers differ

Very similar chemical properties, slightly different physical properties

What structural isomers to chain isomers make

Isomers of C4H10

Features of positional isomerism

Same carbon skeleton, same functional group, different position of functional group

How do properties of positional isomers differ

Similar chemical properties, different physical properties

Features of functional group isomers

Same molecular formula, different functional groups, different chemical properties, different physical properties

Examples of chain isomers

Butane, 2-methylpropane

Examples of positional isomers

Pent-1-ene, pent-2-ene

Examples of functional group isomers

Alcohols+ esters, aldehydes+ ketones, acids+ ester

When does geometrical isomerism occur

In alkenes

What type of isomerism is geometrical isomerism

Stereoisomerism

What causes geometrical isomerism

Restricted rotation between c=c bonds

2 types of geometrical isomerism

Cis (z) trans (e)

Cis/z

Atom/group are on thee same side of the double bond

Trans/e

Groups are on opposite sides of the double bond

When are cis and trans used

When the same 2 groups come off each carbon

When is e/z used

Are generic- determine if its e or z based on size eg if bigger and smaller are same sides is z and if two smaller on one side and one bigger on other side is e

Isomer number formula for up to 7 carbons

2^(n-4 )+1 where n = number of carbons

Isomer equation for 8 carbons

2^n-4 + 2

Isomer formula for 9 carbons

2^n-4 +3

Isomer formula for 10 carbons

2^n-4 +1 + n where n= 10