Question

water photo decomposition reaction and water electrolytic decomposition reaction

Answer 1

Photo decomposition is the reaction in which decomposition reaction occur in presence of light.
for e.g.
2AgBr(in presence of sunlight)→2Ag+Br
Electrolytic Decomposition is the reaction in which decomposition reaction occur because of electric currect.
For e.g.
2H2O (in presence of electric current)→2H2+O2

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