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Gaffer Variety:
Elements 8 SN2 010:
By Willie Gaffer:
Nitrogen is a nonmetallic element occurring as a colorless, odorless, almost inert diatomic gas, N2. It is found in some minerals and in all proteins. It has many applications in manufacturing. Products include ammonia, nitric acid, TNT, and fertilizers. It has an atomic number of 7, an atomic weight of 14.0067, a melting point of -209.86°C, a boiling point of -195.8°C, and valences of 3 and 5.
Nitrogen is another element that is important in gasoline engine chemistry. It is dawn naturally into the engine though the carburetor as part of the air flow, the largest part. It comprises about 80% of the earth’s atmosphere. Of course, the problem with that is, in the heat of the burn, nitrogen will combine with the oxygen to form oxides of nitrogen. These are deadly to life in concentrations. They become the smog we find in urban areas.
Its most important use may be as a fertilizer. It is essential to all plant development. In that plant growth process, the plants turn nitrogen into proteins and the plants are then consumed by animals. The proteins then become the muscle tissues and other tissues of the animals. That muscle tissue is the stuff we humans love to put on the grill. Some plants actually produce more nitrogen than they use. These are what we call the leguminous plants. Among them are peas, beans, and peanuts. This nitrogen is actually not produced by the plants, but by a bacterium that lives in the roots of these plants. They assimilate nitrogen from the air and fix it in the soil around the plant. The nitrogen cycle is completed by plant decay, animal decay, and animal excrement putting nitrogen compounds back into the soil and water.
I have thought one way of getting nitrogen out of the air intake of engines would be to somehow fix it. Some commercial fertilize is produced by using electrical discharge to fix nitrogen. The more common way of producing nitrogen fertilize is by fractional distillation of liquid air. These are just two ways to remove nitrogen from air. Neither seems to be practical for our use now, but the concepts might bring other ideas out of the black hole of my mind.
Chemically, nitrogen gas is quite inert, especially at ordinary temperatures. Owing to its inertness, nitrogen gas is used in the chemical industry as a diluent or as a blanket to exclude oxygen and moisture. The low temperature (and inertness) of nitrogen in the liquid state make it suitable for freeze-drying food and as a refrigerant when transporting perishable commodities. Liquid nitrogen has also proved useful in cryogenic research.
Much nitrogen is combine with hydrogen to produce ammonia, NH3, in commercial quantities. This is a colorless gas that stinks pretty bad and can be deadly in concentrations.
Oxygen is a nonmetallic element, which makes up about 20 percent of the atmosphere by volume. In that form it occurs as a diatomic gas, O2. We also find oxygen in a bunch of compounds. Water and iron ore are two. It combines with most elements, is essential for plant and animal respiration, and is required for nearly all combustion. The atomic number is 8, the atomic weight is15.9994, the melting point is -218.4°C, the boiling point is -183.0°C, and its density at 0°C is 1.429 grams per liter. Oxygen has a valence of 2.
This is the fourth and final element that we must deal with in engine chemistry. The four elements are hydrogen, carbon, nitrogen, and oxygen. Of course, oxygen is essential to combustion. Nothing can burn without it. Burning is actually a process of rapid oxidation wherein the fuel is converted to some kind of oxide. The kind of oxide we get will depend on the fuel. With pure hydrogen and oxygen, all we can possibly get is water, H2O. If we burn carbon, we cannot but help producing carbon dioxide, CO2. If we mix in a lot of nitrogen, we are sure to get a lot of oxides of nitrogen. Isn’t it odd how chemistry follows natural law like that? There is no magic to it. If we put garbage in, we will get garbage out.
Our auto engine is not the only thing that produces carbon dioxide. We and other animals produce it when we breathe. For sure, we cannot stop anyone from breathing, even if we sometimes wish we could, but we should be able to stop engines from producing this dangerous compound. It’s a matter of understanding the chemistry and applying it in the right way.
It’s not all bad. We must simple look at and understand the oxygen cycle. Oxygen is essential to respiration and we need free oxygen in the air for this to happen. The major way we get that oxygen is through an elaborate process called photosynthesis. In this process thee carbon dioxide produced by respiration and other sources is absorbed into the green leaves of plants. The plants combine this CO2 with water, H2O in a complex process to produce glucose, (C6H12O6) for their own growth. A byproduct of that process is oxygen. Simplified, the process is 6CO2 + 12H2O + energy -> C6H12O6 + 6O2 + 6H2O. Where does it get the energy to do this? From direct sunlight. So, you can see we need CO2. We just don’t need so much of it.
Commercial oxygen is produced in much the same way we produce nitrogen, by the fractional distillation of liquid air. Oxygen has become essential in medicine and it is necessary to many industrial processes. It forms covalent bonds with many other elements. Carbon and water are just two.