oragnic chemistry identifying groups

Test for alkenes

reaction with bromine water

Alkene reagent

Bromine solution (Br2 aq)

Alkene condition

Room temperature

Observation Alkene

The brown colour of bromine water disappears (decolonizes) as it adds across the double bond

Alkene new functional group

Haloalkane

Alkynes identifying is the same as,….

Alkenes

Alcohol test

Oxidation

Alcohol reagent

Acidified potassium dichromate (K2Cr2O2 acidic) or acidified potassium permanganate (KMnO4 acidic)

Alcohol condition

Heating under reflux

Alcohol observation

The Orange dichromate ion (Cr2O7^-2) or purple permanganate ion (KMnO4^-1) is reduced and changes colour while the alcohol is oxidise to a different functional group e.g. primary alcohol to carboxylic acid

Alcohol new functional group

Carboxylic acid

Carboxylic acid test

Reaction with strong bad and a metal

Carboxylic reagent

Sodium carbonate (Na2CO3) or bicarbonate (NaHCO3) solution

Carboxylic acid condition

Room temperature

Carboxylic acid observation

Effervescent (bubbling) of carbon dioxide (CO2) gas occurs as the acid reacts with the carbonate

Carboxylic acid new functional group

Salt

Amine test

Reaction with week acid

Amine reagent

Dilute hydrochloric acid (HCl aq)

Amine condition

Room temperature

Amine observation

An amine will react to form a salt that is soluble in water, whereas a neutral compound may not react. The pH will decrease as the basic amine is neutralised

Amine new functional group

Ammonium salt