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Hydrocarbons – compounds that contain only carbon and hydrogen
Types of Hydrocarbon according to Structure
1. Aliphatic – open-chain
2. Cyclic – close chain
Saturated hydrocarbon – contains sigma bond
– includes alkanes and cycloalkanes
Unsaturated hydrocarbon – contains a sigma and pi bond
– includes alkenes, cycloalkenes, alkaynes, cycloalkynes, and aromatic

Ignition test – hydrocarbons exhibit luminous flame with soot due to incomplete
combustion.

Baeyer’s Test – Test for Unsaturation
- Brown precipitate (MnO2)
Alkene and alkyne gives positive results

Electrophilic Aromatic Substitution – The most common type of reaction in aromatic
compounds.
Why aromatic compounds do undergoes aromatics substitution?
If addition reaction occurs, the aromatic ring would be lost. When
substitution occurs, the stability of the aromatic ring is retained.
o Bromination of acetanilide illustrates electrophilic aromatic substitution wherein
the benzene ring contains an activating ortho-para director.
o Cloudiness or white precipitate
Alcohols – compounds that have hydroxyl groups bonded to saturated, sp3 hybridized, carbon
– general formula: ROH
Classification of Alcohol according to Alkyl Group
1. Primary (1O)– the carbon containing the –OH group is attached to one alkyl group.
2. Secondary (2O)– the carbon containing the –OH group is attached to two alkyl
groups.
3. Tertiary (3O) – the carbon containing the –OH group is attached to three alkyl
groups.

Chromic Acid Test – Test for primary and secondary alcohol
– Turquoise (blue-green) solution

Lucas Test – Test for tertiary and secondary alcohol
- Cloudiness; emulsion

Esterification – Gummy odor
o Methanol + Salicylic acid → Methyl salicylate

Test for Methyl Alcohol – Red/Pink picric ring

Iodoform Test – Test for methyl ketone
– Yellow precipitate

Acrolein Test – Test for Glycerol
o Pungent odor – due to propenal
Phenols – aromatic compounds with the –OH group directly bonded to benzene ring.
– More acidic than alcohol – due to resonance stabilization.
– The presence of electron-withdrawing groups such as NO2 and CN can further
enhance acidity.

Solubility in Alkali
o Soluble in water

Reaction with ferric chloride
o Phenol – violet solution
o Catechol – dark green solution
o Thymol – yellow solution
o Naphthol – light brown solution

Bromine Water Test
o Phenol – white precipitate
o Salicylic acid – no precipitate

Phenolphthalein Formation
o Indicator
o Acidic in nature
o Turns pink in the presence of a base

Millon’s Test – test for phenol
Aldehydes, Ketones and Saccharides
Aldehydes – contains a carbonyl group at the end of the carbon chain.
– RCOH
Ketones – contains a carbonyl group in the middle of the carbon chain.
– RCOR

2,4-dinitrophenylhydrazine Test - Test for Carbonyl group

Sodium Bisulfate Test- Test for Aldehydes and Methyl Ketones

Schiff’s Test – Test for aldehydes
o Purple solution
Tollen’s Test – Test for aliphatic and aromatic aldehydes
o Silver mirror


Fehling’s Test – Test for Aliphatic aldehydes
o Brick red precipitate (cuprous oxide)

Sodium Nitroprusside Test – Test for presence of acetone
o -Wine red solution

Iodoform Test – Test for Methyl Ketones

Special test for Benzaldehyde
o Formation of crystals

Molisch Test – General test for Carbohydrates
o Violet ring (2nd layer)

Bial’s Orcinol Test – Test for pentose

Phenylhydrazine Test – Test for reducing sugars
o Osazone crystals

Optical rotation – property of a substance that could rotate the plane of polarization of
a beam of polarized light.
Carboxylic acid – RCOOH
– React with strong bases (NaOH, KOH) to form water soluble salts.

Test for carboxylic acid
o Acetic acid – soluble in water and NaOH
o Stearic acid – insoluble in water and NaOH

Reaction with sodium carbonate
o Effervescence – release of carbon dioxide

Esterification
o Acetic acid + n-propyl alcohol → propyl acetate
o Benzoic acid + n-propyl alcohol → propyl benzoate

Reaction with Neutral FeCl3
o Acetic acid – red-orange precipitate
o Tartaric acid – effluence of red-orange precipitate

Special Test for tartaric and citric acid
o Citric acid – green solution → colorless solution
o Tartaric acid – brown solution → colorless solution

Hydroxamic test for esters
o Magenta or burgundy solution

Hydrolysis reactions
o Acetic anhydride – blue litmus paper → red litmus paper
o Acetamide – red litmus paper → blue litmus paper