Silver halides like silver chloride, silver bromide and silver iodide are photosensitive in nature. Silver chloride is known to quickly disintegrate into chlorine gas and silver metal when exposed to sunlight. Silver halides are light sensitive chemicals and are commonly used in photographic film and paper. Students can observe the change in colour when silver chloride which is white in colour changes to grey as it decomposes to metallic silver and elemental chlorine gas upon exposure to sunlight. This reaction is called photochemical decomposition. Hence, silver chloride is stored in dark coloured bottles that stops the sun rays from reaching the contents of the bottle and prevents the decomposition of silver chloride to chlorine and silver. Students can learn more about observable physical and chemical changes in practical experiments of solutions, compounds, gases and precipitates in chemistry on Vedantu. Study material for chemical reactions, concepts, formulae and chemical structures at play behind these experiments is available to students to download for free for exam preparation and revision on the Vedantu website and app.