sentence: for example , lithium dissolves in liquid ammonia to give a solution of lithium amide : self-dissociation like water , ammonia undergoes molecular autoionisation to form its acid and base conjugates : at standard pressure and temperature , k = ( ) ( ) = 10 combustion the combustion of ammonia to nitrogen and water is exothermic : the standard enthalpy change of combustion , δ h ° c , expressed per mole of ammonia and with condensation of the water formed , is − 382.81 kj/mol .