Ancient researchers performed a huge number of experiments, some of them led to failure teaching lot of things, and the others left their marks for their present and the future era. Researchers earlier had the habit to test the results of the experiments on themselves, risking their life at times. But then, discoveries happen this way.
One of the major discoveries of the “Nitrous Oxide (N₂O)”, popularly known as the “laughing gas” in the 18th century led to a drastic change especially in the field of medical science. It was discovered accidentally when a British chemist, Humphrey Davey inhaled the gas formed by the sprinkling of nitric acid over iron filings and found the results were mystical. He was suddenly in a state of euphoria and felt a strange tingling sensation in his arms and legs. He was so ecstatic by the feeling that he was unable to control his laughter, and so nitrous oxide was named as the “laughing gas”. He felt sleepy after few minutes due to the anesthetic effects of nitrous oxide. Davy noted the anesthetic effects of the gas: “As nitrous oxide in its extensive operation appears capable of destroying physical pain it may probably be used with advantage during surgical operations in which no great effusion of blood takes place.”
N₂O wasn’t used for medical applications till 40-50 years since it was been discovered. Instead, it became a source of entertainment in British parties where the gas was inhaled by people in small amount to enjoy its euphoric effects. Also, charges were applied for the inhalation of small amount of N₂O and huge public used to gather as it became the centre of attraction for people those days.
N₂O is a clear colorless gas with slightly sweet odor. Earlier methods of the synthesis of N₂O include the sprinkling of nitrous oxide over iron filings as discussed above or the reaction of sulphamic acid with nitric acid. But there was a danger of explosion as well as the requirement of noble metal catalysis. So presently N₂O is synthesized as follows:
This reaction occurs at 40-100° efficiently. But in actual practice, 50% N₂O is used with remaining 50% of oxygen for medical applications. The anesthetic effects of nitrous oxide can be seen in about 3 minutes. Though, at low temperatures, N₂O is a non-flammable gas but at temperatures above 650°C, it can explode as well.
An interesting fact to know about is the emission of N₂O gas by the bacteria in oceans and soil. Also, another best thing about N₂O is that none of the people including the heart patients, diabetics etc. are allergic to the small amount of this gas used for medical applications. Nitrous oxide is also used in food industry in cooking spray as a propellant. It is also used to fill the bags of potato chips so as to make the bags puffy preventing the chips from being puffed. It has a wide range of applications in other fields as well.
Though, used in small amount nitrous oxide has a wide range of applications but if inhaled in large amount can be very adverse and can take your life as well. So due to the adverse effects of N₂O, it is now a controversial topic whether to continue using it for medical applications or not. Also, the exposure of N₂O to the atmosphere can lead to atmospheric change as it is a considerable and effective greenhouse gas. So these are some of the points that need to be taken care of.
Ending with the amazing words quoted for the laughing gas by a poet “Robert Southey” for its euphoric effects:
“I am sure the air in heaven must be this wonder working gas of delight.”