What do you understand by spontaneous and non-spontaneous processes?
Spontaneous process. A process which has a natural tendency to take place either by itself or after initiation under a given set of conditions is known as a spontaneous process. For example,
(i) Sugar dissolve in water and forms a solution.
Sugar + water 
Solution of sugar in water
(ii) In the domestic oven, coal keeps on burning once ignited.
Non-spontaneous process: A process that has no natural tendency or urge to take place is called non-spontaneous process. However, many non-spontaneous processes can also be made to take place by supplying energy continuously from some external sources. For example:
(i) Water can be made to flow uphill by the use of an electric motor pump.
(ii) Electrolysis of water to separate it into pure hydrogen and pure oxygen.
