Silver is more likely to tarnish near a petroleum refinery than in a place far away . Explain why?
Silver articles become black after some time when exposed to air. This is because silver reacts with sulphur in the air to form a coating of silver sulphide.
Now petroleum, apart from hydrocarbons also contains a small amount of sulphur. During petroleum refining, this sulphur is released. Thus air in the vicinity of a petroleum refinery has a higher concentration of sulphur than other places. This is why silver is more likely to get tarnished near a petroleum refinery than in a place far away.