Functional groups

Boiling point of alcohols

Higher than those of alkanes with similar molecular weights

Largely from alcohols being able to form hydrogen bonds

Increases as carbon chain increases due to increased dispersion forces

Solubility of alcohols (3 or less carbons)

Hydrogen bonds are most significant

Form hydrogen bonds with water

Soluble

Solubility of alcohols with more than 3 carbons

Dispersion forces increases as length of non-polar hydrocarbon tail increases

Unable to form hydrogen bonds with water

Solubility in water decreases and solubility in non-polar solvents increases.

Intermolecular forces of ketones and aldehydes

Dispersion forces

Dipole-Dipole interactions between polar groups

Boiling points of ketones and aldehydes

Higher boiling point than alkanes of similar mass due to dipole-dipole interactions

Lower boiling points than alcohol because they don’t form hydrogen bonds

Higher boiling point as the number of carbon atoms and dispersion forces increases

Solubility of aldehydes and ketones

• With one to four carbons are soluble in water

• With five or more carbons are not very soluble in water

• Form hydrogen bonds with water between carbonyl oxygen and hydrogen atoms in water

Boiling point of carboxylic acids

Pure carboxylic acids form hydrogen bonded dimers

Dimers are stable species with a molar mass double that of a single carboxylic acid molecule

Increase in size results in an increase in dispersion forces

Boiling point of carboxylic acid is much higher than that of other organic molecules of similar molar masses

Solubility of carboxylic acid

Short chain carboxylic acids are soluble in water

Hydrogen bonding occurs between the water molecules and both the groups on the carboxylic acid molecule

Intermolecular bonding of esters

Have lower melting and boiling points than carboxylic acids of similar size because of hydrogen bonding

Esters only form dispersion and dipole-dipole forces

Esters have poor solubility in water

Esters in an acid solution

If an ester is boiled in acid solution, then the ester bond will be broken, reforming the alcohol and carboxylic acid

Esters in a basic solution

If an ester is boiled in a basic solution, then the ester bond will be broken, reforming the alcohol and conjugate base of the carboxylic acid (a carboxylate ion)

Functional group of amide

-CONH₂ like carboxylic acid but replace the OH group for amino group