Basic Organic

Hydrocarbons

Compound of Hydrogen and Carbon only

Saturated

Only single bonds

Unsaturated

Containing a multiple carbon-carbon bond

Homologous series

A series of organic compounds w/ the same functional group and similar chemical properties but with each successive member differing by CH2

Functional group

The part of the organic molecule responsible for its chemical reactions

Aliphatic

Containing carbon atoms joined together in straight or branched chains

Alicyclic

Containing carbon atoms joined together in a ring that is not aromatic

Alkanes

The Hydrocarbon homologous series with single carbon to carbon bonds and the general formula CnH2n+2

Alkenes

The hydrocarbon homologous series with at least one double carbon to carbon bond

Alkynes

The hydrocarbon homologous series with at least one triple carbon to carbon bond

Alkyl groups

A side chain formed by removing a hydrogen atom removed from an alkane parent chain

For example CH3, C2H5; any alkyl group is often shown as R

General Formulae

Simplest algebraic formula of a member of a homologous series eg Alkanes: CnH2n+2

Empirical Formula

Shows simplest whole number ratio of atoms of each element present in the compound

Molecular Formula

Shows number and type of atoms of each element present in a molecule

Displayed formula

Formula showing relative positions of all atoms in a molecule + the bonds between them

Skeletal Formula

Simplified organic formula w/ Hydrogen atoms removed from alkyl chains, leaving just a carbon skeleton and associated functional groups

Structural Isomers

Molecules w/ same molecular formula but different structural formula

First 10 alkanes

Methane

Ethane

Propane

Butane

Pentane

Hexane

Heptane

Octane

Nonane

Decane

Naming Branched Alkanes

1. Suffix -ane

2. Identify longest continuous chain of carbon atoms: e.g 4 - But-

3. Identify side chains/ which no. carbon the chains are on. e.g 2 methyl side chains on carbon 2/3 (used lowest 2): 2,2-dimethyl

4. Combine suffix, stem and side chains: 2,2,-dimethylbutane

Naming Alicyclic Alkanes

1. Longest chain

2. Add cyclo

3. e.g Cyclopentane

Naming Alkenes

1. Suffix -ene

2. Longest Carbon Chain: e.g 5: pent-

3. Identify space of double bond: e.g between c2 and c3: 2-

4. Combine: pent-2-ene

Naming Alcohols

1. Functional group -ol

2. Longest chain: e.g 4: Butan-

3. Which carbon: 2-

4. Combine: butan-2-ol

Naming Alehydes

1. Functional Group -al

2. Longest chain: e.g 3: propan-

3. Propanal

Naming Organic compounds w/ Multiple Functional groups

1. Longest Chain: e.g 4, Butan-

2. Functional groups: e.g Halogen on C2: 2-chloro, Methyl on C2: 2-methyl

3. Stem + prefixes (alphabetical order) e.g 2-chloro-2-methylbutane

Bond Angles in Alkanes

109.5º due to each C pair being surrounded by 4 bonding pairs in 4 sigma bonds

Effect of chain length on bpt

London forces are between molecules

As chain length increases, molecules have larger SA - more surface contact possible between molecules

London forces greater → more energy required to overcome

Bpt increases with chain length

Effect of branching on bpt

Isomers of alkanes: same molecular mass

Branched lower bpts