Will it be possible for you to decompose water by heat or light energy

Will it be possible for you to decompose water by heat or light energy ? If you pass current from a 6 volt battery is decomposition of water possible ?

Ans. If you take pure water it is not possible to decompose water by heat or light energy or using a 6 volt battery. But if you add a few drops of acid to water then it is possible to decompose acidulated water by passing current from a 6 volt battery.