Properties of alcohols

• Polarity

  Alcohols have a polar O-H bond because of the difference in electronegativity of the oxygen and hydrogen atoms. Alcohol molecules are therefore polar.
• Volatility and boiling point

  In the liquid state, intermolecular hydrogen bonds hold the alcohol molecules together. These bonds must be broken to change the liquid alcohol into a gas. This requires more energy than overcome in the weaker London forces in alkanes, so alcohols have a lower volatility than alkanes with the same number of carbon atoms.
• Solubility in water

  Alcohols are soluble in water as hydrogen bonds form between the polar -OH group of the alcohol and the water molecules.
• Secondary alcohols have the -OH group attached to a carbon atom that is attached to one hydrogen atom and two alkyl groups.
• Tertiary alcohols have the -OH group attached to a carbon atom that is attached to no hydrogen atoms and three alkyl groups.