Write an equation for decomposition reaction where energy is supplied in the form of heat/light/electricity

Chemical decomposition : A chemical reaction in which a single substance splits into two or more substances is called chemical decomposition.
For decomposition reaction where energy is supplied in the form of :
a) Heat : On heating calcium carbonate decomposes into calcium oxide and carbondioxide.

OR

b) Light: Silver bromide decomposes to silver and bromine in sunlight.

OR

c) Electricity : On passing the electricity, water dissociates to hydrogen and oxygen.