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Physical and Bond Properties

Alcohols and ethers can formally be considered as derived from water by replacing one or two of its hydrogens by carbon groups.

Bond angles are compatible with an sp3 hybridization of the oxygen.

Geometry of water, methanol and dimethyl ether (bond angles of 104.5°, 108.9° and 111.7°) and their boiling points: hydrogen-bond association decreases and disappears in the ether

The hydroxyl group confers polarity to the molecule and the possibility of forming hydrogen bonds. The carbon part is non-polar and hydrophobic. The longer the carbon chain, the lower the solubility of the alcohol in water and the higher in non-polar solvents.

The OH group is hydrophilic and the carbon chain hydrophobic: methanol is very soluble in water and poorly soluble in hexane; a long-chain alcohol, the opposite

Alcohols form strong hydrogen bonds. That's why they have high melting and boiling points compared to the corresponding alkanes.

Table of physical properties of alcohols (methanol to neopentyl alcohol) compared with 2-chloropropane and propane: melting and boiling points and solubility in water