Ammonia in nitrogen cycle Susana Inzunza

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What is nitrogen?Nitrogen, symbol N, is the chemical element of atomic number seven. At room temperature, it is a gas of diatomic molecules and is colorless and odorless. Nitrogen makes up around 78% of the air we breathe.Nitrogen is present in all living things.Nitrogen gas is used in food storage to preserve packaged foods. It is also used to produce electronic parts for industrial purposes.

January 28,2014

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What is Ammonia?

Ammonia, is a compound of nitrogen and hydrogen( Formula: NH3).It is a colorless gas with a strong smell. Ammonia is a significant provider of the nutritional needs of organisms in the Earth

by serving as a antecedent to food and fertilizers. Ammonia is also a building-block for the synthesis of many pharmaceuticals and is

used in many commercial cleaning products. Ammonia is both acidic and hazardous.

January 28, 2014

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Nitrogen Cycle The nitrogen cycle begins with the element nitrogen in the air. Nitrogen in the air becomes a part of biological matter mostly through the actions of bacteria and algae in a process known as nitrogen fixation. Legume plants such as clover, alfalfa, and soybeans form nodules on the roots where nitrogen fixing bacteria take nitrogen from the air and convert it into ammonia, NH3. The ammonia is further converted by other bacteria first into nitrite ions, NO2-, and then into nitrate ions, NO3-. Plants utilize the nitrate ions as a nutrient or fertilizer for growth. Nitrogen is incorporate in many amino acids which are further reacted to make proteins. Then other bacteria in the soil carry out a process known as denitrification which converts nitrates back to nitrogen gas. A side product of this reaction is the production of a gas known as nitrous oxide, N2O which is also known as “laughing gas”. It is also a greenhouse gas which contributes to global warming.

January 28,2014

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Nitrogen fixationNitrogen fixation is a process where nitrogen (N2) in the atmosphere is converted into ammonium (NH4). The fixation process frees the nitrogen atoms from their diatomic form (N2) to be used in other ways.

Nitrogen fixation formula

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Bacteria used to produce ammonia  Rhizobium bacteria are used to produce ammonia. Plants that contribute to nitrogen fixation include the legume family including kudzu, clovers, soybeans, alfalfa, lupines, peanuts, and rooibos. They contain symbiotic bacteria called Rhizobium inside  nodules in their root systems, producing nitrogen compounds that help the plant to grow and compete with other plants. When the plant dies, the nitrogen is released; making it available to other plants and this helps fertilize the soil. 

There are also certain cyanobacteria that are able to fix nitrogen such as heterocyst. They are specialized nitrogen-fixing cells formed during nitrogen starvation by some filamentous cyanobacteria. They fix nitrogen from dinitrogen (N2) in the air using the enzyme nitrogenase, in order to provide the cells in the filament with nitrogen for biosynthesis.

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Traditional In many traditional and organic farming practices, fields are rotated through various types of crops, which usually includes one that entirely contains clover or buckwheat which are often referred to as "green manure".When a plant or animal dies, or an animal expels waste, the initial form of nitrogen is organic. Bacteria or fungi convert the organic nitrogen within the remains back into ammonium (NH4

+), with a process called ammonification.

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Industrial fertilization The Haber Process, developed by Fritz Haber, combines nitrogen from the air with hydrogen derived mainly from methane into ammonia. The reaction is reversible and the production of ammonia is exothermic.

January 28, 2014

This conversion is typically conducted at 15–25 MPa (2,200–3,600 psi) or 150–250 bar and between 300–550 °C (572–1,022 °F), as the gases are passed over four beds of catalyst, with cooling between each . On each pass only about 15% conversion occurs, but any gases that are not reacting are recycled and an overall conversion of 97% is achieved.

Traditional Industrial•if bacteria was the only source used people would have to use more land to supply enough crops to feed humans.•It’s a balanced cycle and does not have a negative impact on nature.

•The Haber process now produces 500 million short tons of ammonia per year.•Industrial nitrogen fixation is detrimental to our habitat. •The Haber process is quicker but uses energy.