alcohols

• alkanes have non-polar bonds because the electronegativity of hydrogen and carbon are very similar • alkanes are non- polar • alkanes have very weak London forces • alcohols have a large difference in electronegativity of the O and H atoms • alcohols are polar • alcohols have weak London forces and stronger hydrogen bonds

• less volatile • higher melting points • greater water solubility • differences become much smaller as the length of the carbon chain increases

in liquid state, intermolecular hydrogen bonds hold the alcohol molecules together • thee bonds must be broken in order to change from liquid to gas • more energy needed that overcoming the weaker London forces in alkanes • alcohols have lower volatility than the alkanes

• alcohols are soluble in water as they can form hydrogen bonds with water • alkanes are non- polar so cannot • as the chain length of alcohols increase, the solubility decreases as the influence of the O-H group decreases

• reaction is exothermic, releasing a large quantity of energy in the form of heat • as the chain length increases, an increase in heat released per mole

orange to green

reaction in which water molecules is removed from the starting material