question_answer

Water decomposes by absorbing \[286.2\,kJ\] of electrical energy per mole. When \[{{H}_{2}}\] and\[{{O}_{2}}\] combine to form one mole of \[{{H}_{2}}O,\,\,286.\,2kJ\]  of heat is produced. Which law is proved? What statement of the law follows from it?

Answer:

              Law of conservation of energy (or 1st law of thermodynamics). Def. Energy can neither be created or destroyed, although it may be converted from one form to another.