Nitrous Oxide

From Chempedia

Heather Buffie
Kirsten Jensen
Varun Verma
Jacob Christianson

Nitrous Oxide [ -http://www.chm.bris.ac.uk/motm/n2o/n2o.mol](ii)

(laughing gas)
(N₂O)
Blue = Nitrogen
Red = Oxygen

Nitrous Oxide, can also known by N₂O or dinitrogen monoxide, a colorless gas with a semi sweet odor.⁽ⁱ⁾ The gas was first discovered by the English scientist, Joseph Priestly in the nineteen seventy three. In the initial reaction, N₂O was produced by heating ammonium nitrate (NH₄NO₃) in the by filings of iron, then the product passed off was NO, nitric oxide. The NO was then was passed through water in order to remove any toxic byproducts.⁽ⁱ⁾ This was that initial reaction.

2NO + H₂O + Fe => N₂O + Fe(OH)₂⁽ⁱⁱ⁾

Nitrous oxide is an interesting molecule that can do a variety of things. It can be used in the human body and in automobiles. They are used differently in those two areas, though. The way that it is used in the body is to numb the sensation of pain from the inhalation of the gas. Then, the gas can also be used in several functions outside the human body. That would be from the uses in automobiles engines and the negative effect of greenhouse gases.

At normal room temperature and conditions nitrous oxide is non-reactive with most substances. However once the temperature or pressure is raised nitrous oxide can become a very volatile substance.⁽ⁱ⁾ When sufficiently heated, N₂O decomposes in to nitrogen gas (N₂) and oxygen gas (O₂). When this decomposition occurs it is a very exothermic reaction.⁽ⁱⁱ⁾ This process occurs in the cylinders of the combustion engine. When this occurs two moles of N₂O are used to produce three moles of total gas. The reaction shown below is that of the nitrous oxide breaking down in to nitrogen gas and oxygen gas.

2N₂O(g) => 2N₂(g) + O(g)⁽ⁱⁱ⁾

"This provides an extra boost to the piston stroke because it delivers more oxygen than atmospheric air by breaking down at elevated temperatures, thus allowing the engine to burn more fuel and air."⁽ⁱ⁾ Additionally, the N₂O used in race cars is stored in a liquid form because evaporation of a liquid on the intake manifold causes a negative temperature change.⁽ⁱ⁾ The result is a smaller, denser charge of gas which can reduce denotation, as well as increase the engine’s available power.⁽ⁱ⁾ The reason that this is allowed to happen in the automobile is due to the chemical properties of the nitrous oxide. The gas is able to disassociate at low temperature but a high pressure that will allow combustion to occur.^(iv) This can also create a negative effect if the gas is not used properly. If the engine does not combust all the nitrous oxide, the remaining gas will eat away at the metal block, cylinder walls, and intake.^(iv) This will lower the force that it would take to break one of these elements. Then once the gas is used again, when it will increase the power of the engine by 100-300% one or more of these elements have the possibility of failing.⁽ⁱⁱⁱ⁾ This is a tremendous safety risk to the user and anyone in the area around the automobile when the nitrous oxide system is engaged.

One of the most well known uses of nitrous oxide is its use as a pain killer in dentistry and surgery, you may not know it as nitrous oxide though, because it is more commonly called laughing gas.⁽ⁱ⁾ This is due to the fact that is can and usually will cause spontaneous laughter. It does though give off anesthetic and analgesic effects.⁽ⁱ⁾ The reason that these effect occur is because it can increase blood flow by dilating blood vessels and arteries, bring in endogenous pain killers to the location of the pain.⁽ⁱⁱ⁾ At that point the nitrous oxide will numb the pain receptors, thus allowing the human body to not feel the pain that they may be in.⁽ⁱ⁾ However, with this being said the individual is still responsive to verbal commands.⁽ⁱ⁾ That is the reason that it is used in dentistry, it allows the patient to not feel the discomfort while still allowing the dentist to work and communicate with the patient. The side effects of the gas are numerous, though. Some are expected and some are not. They include dizziness, disassociation, temporary loss of motor control, and slight nausea.⁽ⁱⁱ⁾ Many of the side effects of the gas cause the individual to seem as though they are under the influence of alcohol. The reasons the side effects and the expected effects occur are not completely understood. The nitrous oxide molecules interact with the plasma membranes of the nerve cells in the brain. This effects the communication between cells across their synaptic gaps.^(v) These effects are similar to that of a B12 deficiency.^(v) The nitrous oxide can be used in different proportions to achieve different results. High concentration of nitrous are needed because it is generally a weak anesthetic.⁽ⁱ⁾ It can be used as a mild sedative at a 50/50 mix ratio, or it can increase to an 80/20 mix ratio for a strong sedative.⁽ⁱ⁾ The ratios that are being discussed are that of the mixture of gas to that of oxygen.⁽ⁱⁱⁱ⁾ This sedative mix is what is used by dentists and doctors. The ratios vary depending on the procedure that they are performing.

Nitrous oxide is safe when the procedure is done in the hands of medical practitioners. However, it did become common for individuals to get themselves high on nitrous oxide. This was not safe. The gas when pure is not toxic, although death can still result if not enough oxygen is brought to the lungs while the nitrous oxide is inhaled.⁽ⁱ⁾ This is a very addictive product. The reason is that the effect from the inhalation of the gas are only experienced for a short time, about 60 seconds.⁽ⁱ⁾ When the nitrous oxide is taken directly a tank charger by an individual the results can be hazardous. "It has the ability to cause the lungs to collapse from the high levels of pressure, forcing air into the chest cavity, and can cause frostbite because the gas is extremely cold when released."⁽ⁱⁱⁱ⁾ For these reasons, the precaution of exhaling the gas into a balloon before breathing again is what nitrous oxide users will do.⁽ⁱⁱⁱ⁾

Nitrous oxide has been shown as it is used by people. It was first used in automobiles for increased power. Then the gas was shown when humans used it for numbing of pain, and enjoyment of users. However the gas is also found naturally in the environment. This is as a greenhouse gas.Nitrous oxide, like many other nitrogen oxides are found in the atmosphere as greenhouse gases. It is commonly known that greenhouse gases are harmful and are at this point creating global warming. Nitrous oxide however has a very large impact on this because it has "270 times the effect of carbon dioxide on producing global warming."⁽ⁱⁱⁱ⁾ This is the reason that there are many efforts to decrease and try to eliminate the emission of nitrous oxide. However this can not be completely accomplished because nitrous oxide is emitted naturally from most soils and all oceans.⁽ⁱⁱⁱ⁾ Humans, though, can do their part to decrease the emission of nitrous oxide by reducing the cultivation of soil, lowering the production of nylon, reducing the burning of organic matter and fossil fuels.⁽ⁱⁱⁱ⁾ These procedures will lower but not eliminate the amount of nitrous oxide that is emitted in to the atmosphere as a greenhouse gas.

Nitrous oxide is a valuable molecule that can not only be beneficial to people medically, but industrially, as well. Nitrous oxide has many positive and negative effects. There are also risks involved with this gas. The positives are the medical practices that it has helped and the power that it creates for automobiles. The negatives are the harm it can do to engines and the environment. The risks are shown in the users of it risking their lives. Another negative that shows the power that nitrous oxide has it the Oklahoma City Bombing. This happened because there were nitrogen oxides in fertilizer in the back of a truck, the N₂O was contaminated by NO₂ which caused the explosion and demolished the Federal Building.^(iv) Despite this, there are more uses for this molecule that need to be kept in place. There may be many more remarkable uses for this molecule that have yet to be found. The molecule of N₂O is a useful one to everyone; it was seen to be this way a long time ago. The gas is thought to be a great thing on Earth and in heaven. So is said by the words written by the poet Robert Southey "I am sure the air in heaven must be this wonder working gas of delight."⁽ⁱⁱ⁾

Citations

i – Grohol, John. Nitrous Oxide. Last Update: Oct. 5, 2005. Accessed: Oct. 30, 2005. [1]

ii – Eger, I.E., Laughing Gas. Accessed: Sept. 27, 2005. [2]

iii – Nitrous Oxide, Last Update: Sept. 2005. Accessed Sept. 27, 2005. [3]

iv – Sense, Fred. What is Laughing Gas? Last Update: Sept. 2005. Accessed: Sept. 27, 2005. [4]

v – Nitrous Oxide, Accessed: Oct. 30, 2005. [5]