It passes out of the body as a solution in water, which you know as urine. If you have a urea cycle disorder or a genetic disease, your body cannot safely detoxify ammonia. In a scientific breakthrough in , urea was the first natural compound to be artificially synthesized using inorganic compounds. The chemical compound urea is made by heating ammonium carbamide, a combination of ammonia and carbon dioxide, in a sealed container.
The heat dehydrates the compound and forms urea, a crystal-type substance. Claire is a writer and editor with 18 years' experience. She writes about science and health for a range of digital publications, including Reader's Digest, HealthCentral, Vice and Zocdoc. TL;DR Too Long; Didn't Read Urea is the waste produced by humans, as well as many other mammals, amphibians and some fish, when the body metabolizes protein.
Related Articles What is Urea? Physical Properties of Urea. What Is Sodium Lauryl Sulfate? How to Regenerate Activated Charcoal. Extra nitrogen is expelled from the body through urea, and because it is extremely soluble, it is a very efficient process.
The average person excretes about 30 grams of urea a day, mostly through urine, but a small amount is also secreted in perspiration. Physicians found that urea levels can be used to detect diseases and disorders that affect the kidneys, such as acute kidney failure or end-stage renal disease ESRD.
Increased or decreased urea levels, however, do not always indicate kidney problems, but instead may reflect dehydration or increased protein intake. Agriculture More than 90 percent of world urea production is destined for use as a nitrogen-release fertilizer. Urea has the highest nitrogen content of all solid nitrogenous fertilizers in common use Therefore, it has the lowest transportation costs per unit of nitrogen nutrient.
In the soil, it hydrolyses back to ammonia and carbon dioxide. The ammonia is oxidized by bacteria in the soil to nitrate, which can be absorbed by the plants. Urea is also used in many multi-component solid fertilizer formulations. Urea is highly soluble in water, therefore, very suitable for use in fertilizer solutions in combination with ammonium nitrate: UAN , e. For fertilizer use, granules are preferred because of their narrower particle size distribution, an advantage for mechanical application.
The most common impurity of synthetic urea, biuret, must be present at less than 2 percent of the time, as it impairs plant growth.
It is better to make several small to medium applications at intervals to minimize leaching losses and increase efficient use of the Nitrogen applied, compared with single heavy applications. During summer, urea should be spread just before, or during rain to reduce possible losses from volatilization process wherein nitrogen is lost to the atmosphere as ammonia gas. Urea should not be mixed with other fertilizers, as problems of physical quality may result. Because of the high nitrogen concentration in urea, achieving an even spread is important.
The application equipment must be calibrated correctly and used properly. Drilling must not occur on contact with or close to seeding due to the risk of germination damage.
Urea dissolves in water to be applied as a spray or through irrigation systems. In grain and cotton crops, urea is often applied at the time of the last cultivation before planting. In high rainfall areas and on sandy soils where nitrogen can be lost through leaching and where good in-season rainfall is expected, urea can be side or top-dressed during the growing season. Top-dressing is also popular on pasture and forage crops.
In cultivating sugarcane, orea is side-dressed after planting, and applied to each ratoon crop. For irrigated crops, urea can be applied dry to the soil, or dissolved and applied through the irrigation water.
Urea will dissolve in its own weight in water, but it becomes increasingly difficult to dissolve as the concentration increases. Dissolving urea in water is endothermic, causing the temperature of the solution to fall when urea dissolves. When preparing urea solutions for fertigation injection into irrigation lines , dissolve no more than 30 kg of urea per L of water.
In foliar sprays, 0. As urea sprays may damage crop foliage, advice for specific amounts should be sought before use. Low-biuret grades of urea should also be used if urea sprays are to be applied regularly or to sensitive horticultural crops. Like most nitrogen products, urea absorbs moisture from the atmosphere. As with most solid fertilizers, it should also be stored in a cool, dry, well-ventilated area. Chemical industry Urea is a raw material used in the manufacture of many important chemicals, such as:.
Urea has the ability to trap many organic compounds in the form of clathrates. The organic compounds are held in channels formed by interpenetrating helices comprising of hydrogen-bonded urea molecules. This behavior can be used to separate mixtures, and has been used in the production of aviation fuel and lubricating oils, and in the separation of paraffin.
This discovery dealt a severe blow to a widespread belief at the time called "vitalism". This theory maintained that living organisms, like plants and animals, were made of different materials to inanimate objects like rocks.
The belief was that living organisms possessed an unknown 'vital force' that allowed them to fabricate organic chemicals, and since inanimate objects did not possess this force, they could neither create, nor be transformed into the chemicals of life.
Wohler's discovery showed that not only could organic chemicals be modified by chemistry, but that they could also be produced through chemistry as well. In effect, he had shown that we are made of the same materials as the rest of Nature, and are therefore a part of the world around us.
Urea is produced commercially by several steps, which begin with the direct reaction of ammonia with carbon dioxide in a high pressure, high temperature reactor. It is a very important starting material in a number of chemical syntheses, and is used on an industrial scale for the manufacture of fertilisers, pharmaceuticals and resins.
For example, urea is one of the precursors to the various barbiturates , which are widely used as sedatives and sleeping pills. Urea is also used in the production of urethanes , which are then polymerised to form polyurethane foams. Another important application is in the manufacture of resins and polymers. Urea can react with formaldehyde to make the urea-formaldehyde resins, which are highly important in moulded plastics.
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