Carboxylic acids, Alcohols and Esters

How are primary alcohols oxidised to give carboxylic acids?

If a primary alcohol is heated under reflux with acidified K2Cr2O7

The acidified K2Cr2O7 will change colour from orange to green

How are aldehydes oxidised to form carboxylic acids?

If an aldehyde is heated under reflux with acidified Kr2Cr2O7

How do nitriles react to form carboxylic acids?

Nitriles react via hydrolysis

Heat the nitrile under reflux wit a strong acid catalyst

CH3CH2CN + HCl + 2H2O → CH3CH2COOH + NH4Cl

How do carboxylic acids react with metals?

Carboxylic acids react with metals to form a salt and hydrogen gas

2CH3COOH + Mg → (CH3COO)2Mg + H2

How to carboxylic acids react with carbonates?

They form a salt, water and carbon dioxide

2CH3COOH + K2CO3 → 2CH3COOK + H2O + CO2

How do carboxylic acids react with alkalis?

Carboxylic acids react with alkalis to form a salt and water

CH3COOH + NaOH → CH3COONa + H2O

How do alcohols react with carboxylic acids?

They form esters

The process requires heating with sulfuric acid catalyst

How do carboxylic acids react to form alcohols?

Reduction with LiAlH4 or NaBH4

List the reaction used to make alcohols

Electrophilic addition of steam to an alkene, H3PO4 catalyst

Oxidation of alkenes with cold dilute acidified KMnO4 to form a diol

Nucleophilic substitution of halogenoalkanes by heating with NaOH

Reduction of an aldehyde or of a ketone using NaBH4 or LiAlH4

Reduction of carboxylic acid using NaBH4 or LiAlH4 or H2/Ni and heat

Hydrolysis of an ester by heating with a dilute acid or alkali

What’s the general equation for the complete combustion of an alcohol?

Alcohol + oxygen → carbon dioxide + water

What’s the general equation for the substitution of an alcohol to form an halogenoalkane?

Alcohol + Hydrogen halide → Halogenoalkane + water

What other oxide can be used as a substitute a chlorine atom into a halogenoalkane instead of HCl? Give the equation

SOCl2

C2H5OH + SOCl2 → C2H5Cl + HCl + SO2

The reaction does not require heat

State the equation and observations for when phosphorus halides are used in the forming of a halogenoalkane

C2H5OH + PCl5 → C2H5Cl + HCl + POCl3

Steamy fumes of HCl, which can be used as a test for the hydroxy group

Give the equation for forming halogenoalkanes using phosphorus (III) chloride

3C2HOH + PCl3 → 3C2H5Cl + H3PO3

The reaction requires heat

What compounds can be used to make bromoalkanes and iodoalkanes?

PBr3 and PI3

Red phosphorus and bromine or iodine are warmed with alcohol

3C2HOH + PI3 → 3C2H5I + H3PO3

What is the general equation for the reaction of an alcohol with sodium metal?

Alcohol + Sodium → Sodium alkoxide + Hydrogen

How do esters undergo acid hydrolysis?

Heat under reflux with aqueous acid

The ester will be hydrolysed and form into a carboxylic acid and alcohol

The reaction is reversible

How do esters undergo base hydrolysis?

Heat under reflux with a dilute alkali

The ester will be hydrolysed into the salt of the carboxylic acid, and the alcohol

The reaction is not reversible and is faster than acid hydrolysis

What happens when alcohols go through elimination reactions?

They are dehydrated and alkenes are formed

Alcohol → Alkene + Water

A catalyst and heating are required

State the major commercial uses of esters

Perfumes

Solvents

Flavouring