Planar Organic Families Unsaturated compounds Contain a double or a triple bond

Alkenes Name ends in –ene Need to know up to C-4 First 3 are gases, next 1 is a liquid Insoluble in water (do not form hydrogen bonds) Soluble in organic solvents, e.g., cyclohexane Uses = plastics/polymers

Aldehydes Have a C=O bond (carbonyl group) at the end of the carbon chain Name ends in –al Need to know up to C-4 Lower chains soluble in water – C=O bond forms hydrogen bonds with water molecules – but solubility decreases as chains grow longer Soluble in organic solvents, e.g., cyclohexane

C=O bond is highly polar so dipole-dipole forces occur between molecules Higher boiling points than alkanes because of these dipole-dipole forces Uses = benzaldehyde found in almond oil (gives it its scent)

Ketones Have a C=O bond (carbonyl group) in the middle of the carbon chain Name ends in – one Need to know up to C-4 Lower chains soluble in water – C=O bond forms hydrogen bonds with water molecules – but solubility decreases as chains grow longer Soluble in organic solvents, e.g., cyclohexane

C=O bond is highly polar so dipole-dipole forces occur between molecules Higher boiling points than alkanes because of these dipole-dipole forces Uses = industrial solvents (propanone = acetone (nail polish remover))

Carboxylic acids Have a C=O bond (carbonyl group) and a C-OH bond at the end of the carbon chain Name ends in – oic acid Need to know up to C-4 Lower chains soluble in water – C=O bond forms hydrogen bonds with water molecules – but solubility decreases as chains grow longer Soluble in organic solvents, e.g., cyclohexane

Hydrogen bonds occur between molecules forming dimers Higher boiling points than alcohols because of this hydrogen bonding Uses = salts of propanoic & butanoic acid used in food preservation, ethanoic acid used to make cellulose acetate ( photographic film, varnishes)

Methanoic acid is in nettles & ants Ethanoic acid is in vinegar

Esters Have a C=O bond (carbonyl group) and a C-O bond in the middle of the carbon chain called an ester linkage Formed from a carboxylic acid and an alcohol First part of the name comes from the alcohol (right of linkage) Second part of the name comes from the carboxylic acid (left of linkage)

Need to know up to C-4 First few members are volatile liquids (low bp) Lower chains soluble in water – C=O bond forms hydrogen bonds with water molecules – but solubility decreases as chains grow longer Soluble in organic solvents, e.g., cyclohexane Low boiling points because cannot form hydrogen bonds with each other

Uses = fruity smells, ethyl ethanoate is an excellent solvent, polyester is a long chain of esters Formation of esters is a condensation reaction (not an elimination reaction because no new double bond formed)

Aromatics Contain a benzene ring Need to know benzene, methylbenzene & ethylbenzene Insoluble in water (do not form hydrogen bonds) Soluble in organic solvents, e.g., cyclohexane

Uses = used to a widely used solvent but is carcinogenic so no longer used Not all aromatic compounds are carcinogenic – dyes, detergents, indicators (methyl orange & phenolphthaelin), aspirin, ibuprofen etc

Methyl orange: Phenolphthalein:

Aspirin: Ibuprofen: