Effect of light on chemical reaction

answer:

light energy (uv or visible radiation) can initiate or catalyse particular chemical reactions. the greater the intensity of light (visible or ultra-violet) the more reactant molecules are likely to gain the required energy (activation energy) and react, so the reaction speed increases - greater frequency of initiation.

explanation:

answer:

light energy (uv or visible radiation) can initiate or catalyse particular chemical reactions. the greater the intensity of light (visible or ultra-violet) the more reactant molecules are likely to gain the required energy (activation energy) and react, so the reaction speed increases - greater frequency of initiation.

explanation:

light energy (uv or visible radiation) can initiate or catalyse particular chemical reactions.

as well as acting as an electromagnetic wave, light can be considered as an energy 'bullets' called photons and they have sufficient 'impact energy' to break chemical bonds, that is, enough energy to overcome the activation energy.

the greater the intensity of light (visible or ultra-violet) the more reactant molecules are likely to gain the required energy (activation energy) and react, so the reaction speed increases - greater frequency of initiation.

strictly speaking the light (visible or uv) is not a catalyst in the sense that the photons of energy are used up in the chemical changes they induce, the photons cannot be recycled!

examples:

silver salts are converted to silver in the chemistry of photographic exposure of the film.

silver chloride (agcl), silver bromide (agbr) and silver iodide (agi) are all sensitive to light ('photosensitive'), and all three are used in the production of various types of photographic film to detect visible light and beta and gamma radiation from radioactive materials.

each silver halide salt has a different sensitivity to light.

when radiation hits the film the silver ions in the salt are reduced by electron gain to silver.