When silver chloride (AgCl) is exposed to sunlight, it undergoes photodecomposition, breaking down into silver (Ag) and chlorine gas (Cl₂). This reaction is an example of a decomposition reaction caused by light (photochemical reaction).
Chemical Equation:
2AgCl(s) \overset{sunlight}{\rightarrow} 2Ag(s)+Cl2(g)2
Use of This Reaction:
This photochemical decomposition reaction is used in black and white photography. When silver chloride (or silver bromide) is exposed to light, it decomposes to form metallic silver, which creates the image on photographic films.
