What is the chemical name of laughing gas, commonly used as an anesthetic in dental surgery?

The chemical name of laughing gas is nitrous oxide, which has the chemical formula N₂O. It is commonly used as an anesthetic in dental procedures and other medical applications due to its analgesic and sedative properties. Nitrous oxide works by depressing the central nervous system, providing relief from pain and inducing a relaxed and euphoric state, hence the nickname "laughing gas."

This compound is particularly valued in dentistry and surgery because it can be administered safely and effectively, allowing for quicker recovery compared to some other anesthetic agents. Its effectiveness in reducing anxiety during procedures makes it a popular choice among patients and healthcare providers.

The other options listed refer to different compounds with distinct properties and uses. Nitrogen dioxide is a toxic gas associated with pollution, carbon dioxide is a by-product of respiration and combustion, and hydrogen sulfide is a toxic gas with a foul odor often associated with rotten eggs. None of these compounds serve as anesthetics, underscoring why nitrous oxide is the correct answer in this context.