Question

What Chemical Smells like Rotten Eggs?

Answer 1

Hint :An odour is caused by one or more volatilized chemical compounds that are generally found in low concentrations that humans and animals can perceive by their sense of smell. An odour is also called a "smell" or a "scent", which can refer to either a pleasant or an unpleasant odour. The perception of odours, or sense of smell, is mediated by the olfactory nerve.

Complete Step By Step Answer:
Hydrogen sulphide is a colourless, flammable gas that smells like rotten eggs at low concentration levels in the air. It is commonly known as sewer gas, stink damp, and manure gas. As a natural product of decayed vegetation, hydrogen sulphide can occur in groundwater and, depending on the percentage of hydrogen sulphide present, it can produce a moderate or heavy sulphur odour.
At high concentration levels, it has a sickening sweet odour. At extremely high levels, a person can lose their ability to smell the gas and become unaware of its presence. This condition, known as olfactory fatigue, can also occur when people have been exposed to hydrogen sulphide for a longer period of time. Hydrogen sulphide is heavier than air, so it can build up in low-lying areas and enclosed spaces.
In the environment, hydrogen sulphide is produced from the bacterial breakdown or decomposition of dead plant and animal matter, especially when there is a lack of oxygen. It occurs in unrefined natural gas and petroleum, volcanic gases, sulphur deposits, hot springs, and swamps.

Note :
Smell is an important sense as it can alert us to danger like gas leak, fire or rotten food but also is closely linked to parts of the brain that process emotion and memory. Unpleasant and bad smells actually send pain signals to the brain to warn us of possible danger. Smell is vital for survival of most humans and animals as it enables them to track food and water and even communicate.