Photochemistry

• A photochemical reaction is one where light causes a reaction to occur. The higher the light intensity the higher the rate of the reaction.
• Photosynthesis: light provides energy for the reaction and chlorophyll is a dye that absorbs light.
• carbon dioxide + water → (light + chlorophyll) → glucose + oxygen
• Silver salts in photographic film: Silver bromide breaks down, where light strikes the film, so silver is reduced. Silver ions are reduced to silver.