Silver halides darken in light owing to ------- , a property which is primarily responsible for their use in photography.

Options

A. oxidation
B. photochemical decomposition
C. reaction with `N_(2)`
D. photoelectric effect

Answer

B

Explanation

Silver chloried, bromide, and iodide are sensitive to light, and the ready reduction of the silver ion results in a darkening of the solid. (This is why silver compounds and their solutions are stored in dark bottles.)
`Ag^(+) (s) + e^(-) rarr Ag (s)`
This reaction is the key to the traditional photgraphic procedd. In black - and - white photography, it is simply the impact of light on sensitized silver halide microcrystals that initiartes the production of the negitive image. For color photography, the film is composed of layers, with organic dyes acting as color filters for the AgBr. Thus, only light form a particular spectral region will activate the silver bromide in a specific layer.