CHY 104 Lecture Notes - Lecture 8: Reaction Rate, Endothermic Process, Spontaneous Process
Document Summary
Spontaneous processes are processes that take place naturally with no apparent cause or stimulus. Some processes or reactions proceed in only one direction. Gasoline reacts spontaneously with oxygen to form carbon dioxide and water, but water and carbon dioxide never spontaneously react to reform gasoline. A spontaneous process takes place without continuous intervention, according to thermodynamics. The combustion of diamond is thermodynamically spontaneous, but diamonds are considered to last forever. Ice melting spontaneously above 00c ( at 1 atm) A waterfall running downhill, but never up spontaneously. Heat flow from a hot object to a cold object- reverse never spontaneous. Lump of sugar spontaneously dissolves, but does not spontaneously reappear. Iron exposed to water and oxygen forms rust, but rust does not spontaneously change back to iron. So, under same conditions, spontaneous processes cannot occur in opposite direction. Exergonic processes are processes that give up energy as they take place.
