Detection of ammonia can be done using gas sensors. Examples of different application areas of ammonia gas sensing are; environmental monitoring, medical diagnostics, chemical laboratories and detection of ammonia in portable water and wastewater (Timmer et al., 2005). High concentrations of ammonia are easy to detect while for very low concentrations we require different gas sensors operating at different sensing principles. Ammonia gas sensors operate at different temperatures each having a specific detection limit range and response time to measure the ppm and sub-ppm concentrations rapidly. Commercial ammonia sensors make use of different techniques for ammonia detection and can be classified as metal oxide sensors, conducting polymer detectors, catalytic ammonia sensors and optical sensors. The ammonia gas sensors should be considered on basis of cost, maintenance, installation and most importantly specific sensors for the suitable application.
Metal oxide ammonia gas sensors are most widely used and are usually made up of tin i.e. SnO2 sensors (Zakrzewska, 2001). These sensors are inexpensive and are based on the principle of conductance change which arises due to the chemical adsorption of molecules of the ammonia gas on a sensing layer. Selectivity and sensitivity of these sensors towards the ammonia gas can be enhanced by using additives which will drive the adsorption of the gas molecules. Using additives like Au and MoO3 ammonia sensors can achieve the detection limit of 1 ppm. Metal oxides sensors have a detection limit in the range of 1 to 1000 ppm and operates at above 400 0C. In applications like environmental monitoring and detection of combustion gases these sensors are quite helpful.
Sensors made up of polyme...
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...ysis is required. The use of non selective detectors with gas samplers is also a good selective technique to measure ammonia accurately. Table 1 (Timmer et al., 2005) summarizes all the parameters of different types of sensors used for the detection of ammonia. In the methodology section plan of experiments using sensors to detect ammonia in water will be presented. However there are two methods described by the EPA to detect ammonia in water bodies. The first method (Method 350.1) is the distillation method in which the sample is first buffered and then is distilled into boric acid. The ammonia concentration is directly proportional to the indophenol blue which is formed (SEMI, 1993). In the second EPA method (Method 350.2) the sample is distilled into boric acid and the ammonia concentration is determined either titrimetrically or colorimetrically (SEMI, 1993) .
Currently, the United State’s Gulf of Mexico experiences an annual, seasonal “dead zone” as a result of hypoxia. Hypoxia is a low level of dissolved oxygen (<2mg/L) in an area of water. Hypoxia is typically temporary and seasonal, but the low oxygen levels can be devastating to aquatic organisms. Hypoxia occurs in many oceanic waters worldwide, but there is a growing area of concern in our Gulf of Mexico coast. Hypoxia is largely caused by nitrogen fertilizer application for agriculture, with heavy concentrations coming from the Midwestern US. Nitrogen mobilizes as nitrate, and is transported via surface water runoff. The runoff enters tile-drain supported ditches, enters streams and joins the Mississippi river, eventually reaching the gulf. Nitrate mobilization is a problem for human health, and ag. runoff is also often attributed to the contamination of surface and well-water sources in rural areas. High levels of nitrates restrict the ability of red blood cells to carry oxygen. This can harm humans, and is the major cause of infant methemoglobinemia, or “blue baby syndrome”. The safe drinking level standard is 10mg/L.
Nitrous Oxide gas was first discovered by English scientist in 1772 and was first published about in 1776. Through his experiments he discovered Nitrous oxide's analgesic effects in 1800. From 1800 to 1840, Nitrous was primarily used for recreation at traveling public shows, but in 1844-1845 Nitrous was recognized as having some medical use in dentistry. In the late 1800's William James published some accounts of his work with Nitrous Oxide and called its effects of "some metaphysical significance". Nitrous has remained popular throughout the 20th Century and is sold over the counter in small cartridges ("whippets") for making whipped cream and in large tanks for industrial and medical purposes.
This experiment sought to utilize melting point, boiling point, infrared (IR) spectroscopy, and the index of hydrogen deficiency (IHD) to identify the structures of two unknown compounds. To ensure the successful identification of the unknowns, the molecular formula for each compound was found first. What the molecular formula does is that it allows chemists to identify elements present in a compound as well as the quantity of each element. The issue with this is that there are various compounds that share the same molecular compound yet are different in reactivity and connectivity. To resolve this problem, other measures such as finding functional groups based on IR spectroscopy, determining the boiling or melting point of a compound, and identifying the bond/ring structures using IHD are taken.
To complete this lab several chemicals must be measured and transferred to test tubes. First 5.0 mL of 0.200 M Fe(NO3)3 must be diluted to a total volume of 50 mL in a flask. Next 0.0020 M SCN–. This solution is then added to 4 test tubes in 1 mm increments. Each test tube is then put in to
In order to test Natron at various concentrations, we set aside 5 petri dishes for five concentrations: 0% (control), .5%,
Atomic Absorption (AA) Spectroscopy is a quantitative analysis technique that uses the absorption of light through a flame and gaseous chemicals. AA Spectroscopy can be used for a multitude of purposes, most notably finding the concentration of one or a few elements in a compound. AA Spectroscopy can work in two different ways using an open flame and gaseous chemicals or a graphite furnace. Flame AA Spectroscopy works by taking a compound or element and disassociating it into an aqueous solution. The solution is then blown through an incredibly small nozzle which nebulizes the liquid into a very fine mist. The nebulized liquid is then blown through a flame with a very small beam of light passing through it. This light beam detects different elements in the flame and uses the known light absorbance of the element to determine the concentration of the element in the solution. The other form of AA Spectroscopy uses a graphite furnace to heat up and incinerate a sample. A solid compound is placed in the furnace which then heats up to 2000-3000 C effectively atomizing the compound and in the process turning the rest into ash. The light beam is then shot through the furnace as the solid is being heated and subsequently atomized and the machine records the absorbance rate much like the Flame AA Spectroscopy would. The difference between flame and furnace spectroscopy is in the atomization of the sample; because the Flame Spectroscopy uses pressure to atomize the compound, much of the compound is lost when sprayed
In the demo experiment, we placed 10 grams of Ammonium dichromate in the form of a solid before starting the experiment. When the experiment begins the Ammonium dichromate is burned up and then produces Chromium (III) oxide as a solid, Nitrogen gas and water in form of a gas. In the experiment, we combined Zinc Chloride and Sodium Sulfide in which both chemicals are aqueous. The result of the combination was Zinc Sulfide a solid and Sodium Chloride an aqueous solution. In the alternate experiment, we combined Lead (II) Nitrate and Potassium Iodide in which both chemicals are aqueous. The result of the combination was Lead (II) Iodide and Potassium Nitrate.
AQA GCSE Higher Sulphur dioxide (SO2) is a colourless gas, belonging to the family of gases called sulphur oxides (SO_). It reacts on the surface of a variety of airborne solid molecules, is soluble in water and can be. oxidised within airborne water droplets. http://www.doc.mmu.ac.uk/aric/eae/Acid_Rain/Older/Sulphur_Dioxide.html. Many factors can affect the rate of reaction; concentration. temperature, ratio of the substances, amount, stirring, and catalysts. are these factors.
The best way to measure gasses is by creating a closed system for an experiment
- The amount of times the mixture was stirred. We stirred the mixture until the Ammonium Nitrate was dissolved, so the amount of times we stirred after each teaspoon was different.
Contamination of Water and Air. Urbanization enhances the proliferation of industries, automobiles, and agricultural practices. Most toxic air contaminants are produced as we endeavor to fuel our homes, automobiles, factories, energy production facilities, and might also be discovered in indoor cleansing mixtures, and construction supplies. Furthermore pollutants found in gasoline, dry cleaning services, and paint thinners and strippers; som...
The realization of such a service requires that air quality and pollution sensors be deployed across the city and that the sensor data be made publicly available to citizens [1]. 1.1.3 Noise Monitoring Noise is also a form of pollution known as carbon oxide (CO) in the air.
The aim of eliminating nitrogen, whatever the exact form of the nitrogen compounds in wastewater, was the production of nitrogen gas, an inert, water-insoluble gas which is readily separable from liquid media. The need to produce nitrogen gas in nitrogen removal treatment processes is mainly due to the high solubility of nitrogen compounds such as NO3 ~, NH4 + and NO2 ~ present in the removal of nitrogen, nitrogen. It seems that this old paradigm is being challenged. Because nitrogen gas, as in sewage treatment operations, has no economic value, some researchers seek to remove nitrogen compounds in dissolved form. The most promising method for removing dissolved forms of nitrogen compounds is the application of zeolite columns employing adsorption
These are some of the many properties reasons and qualifications for us using sodium in our everyday lives. These are the reasons why sodium is used all around the world to this very day and is also why we use so much of it. Ammonia has an important role in the formation of salt crystallizations which is why it is mentioned in the above paragraph and which so will be used in the experiment that is going to take place to test the importance of ammonia in salt crystallization and to see exactly how the ammonia is going to affect the salt in the end result.
Water quality can be described as the measurement of the condition of water relative to the requirements of humans, animals and plant’s need. When we talk about water quality testing, we are highlighting a critical piece of natural observing for civil engineers in order to create a specific structure or decision. At the point when water quality is poor, it influences almost every single form of life in our planet; going from plants to animals and thereon. Hydrology, in the other hand, is the study of water. It is important to state that hydrology is a critical part for civil engineers to determine and predicting decisions that will affect our biological environment.