Saturday, March 21, 2020

Submitting a Paper Essays

Submitting a Paper Essays Submitting a Paper Essay Submitting a Paper Essay An essay mill (or paper mill) helps students who seek to buy essays and other written homework and to pass off this ghostwritten work as their own. Educators generally see this as a form of academic dishonesty or academic fraud (see also plagiarism). The typical customers of such a service are university and college students. Universities and colleges may investigate papers suspected to be from an essay mill by using Internet plagiarism detection software, which compares essays against a atabase of known essay mill essays and by orally testing students on the contents of their papers.In response, many essay mills state that a unique essay will be composed by a ghost author and pre-screened with plagiarism detection software before delivery, and as such will be undetectable as an essay mill product. Essay mill companies hire university students, graduates, and professional writers to ghostwrite essays and term papers, and solicit business from university and college students by posting advertisements. Until the early 1990s, most essay mill companies were bricks and mortar businesses offering their services by mail-order or from offices located in university or college towns.By the 2000s, most essay mill businesses have switched to an e-commerce business model, soliciting business and selling essays using an Internet website. Companies often provide free sample essays on popular topics, such as Hamlet or The Merchant of Venice, to attract Internet searches. [citation needed] The most basic essay mill service is the sale of a previously-written essay; services dvertise essays that have allegedly gained a good grade and which have allegedly not been used for plagiarism before.Students using essay mill services have little or no legal recourse if the essay they purchase does not act ually receive a good grade. Since submitting a previously-written essay exposes a student to the risk of detection, some students will pay a much higher price for custom-written papers that take into account the course outline, topic, number of sources and any specific grade the student wants.While some students select a high grade on the ghostwritten paper to oost their average, other students with poor grades may choose to purchase a paper that deliberately contains errors, and which will receive a grade such as C+, to reduce the suspicion that they have committed academic dishonesty. The academic community has criticized essay mill companies for helping students to commit academic fraud. Some essay mills have defended themselves against criticism by claiming that they are selling pre-written examples which students can use as guidelines and models for the students own work.In 2002, a UK-based essay mill called Elizabeth Hall material provided by Elizabeth Hall Associates [is] on the understanding that it is a guidance model only. [l] Other essay mills claim that they are scholarly publishing houses that provide students with essays that the student can then cite in the students own work. Although essay mills and the students who use them are considered unethical by many educational professionals, they do not violate copyright law; the mill is the legal copyright holder of the papers, and the papers are licensed to paying students for imited use.As of 2009, no essay mill or client of a mill has been legally prosecuted for engaging in transactions. The mill may, however, hold the student legally responsible in the case where they redistribute the paper to other students without the permission of the mill. In informal settings where students exchange papers without any formal licensing or transfer of copyright, copyright violation may occur, but it is unlikely that the students will press charges, since they would incriminate themselves by doing so.

Wednesday, March 4, 2020

Catalysts Definition and How They Work

Catalysts Definition and How They Work A catalyst is a chemical substance that affects the rate of a chemical reaction by altering the activation energy required for the reaction to proceed. This process is called catalysis. A catalyst is not consumed by the reaction and it may participate in multiple reactions at a time. The only difference between a catalyzed reaction and an uncatalyzed reaction is that the activation energy is different. There is no effect on the energy of the reactants or the products. The ΔH for the reactions is the same.​ How Catalysts Work Catalysts permit an alternate mechanism for the reactants to become products, with a lower activation energy and different transition state. A catalyst may allow a reaction to proceed at a lower temperature or increase  the reaction rate  or selectivity. Catalysts often react with reactants to form intermediates that eventually yield the same reaction products and regenerate the catalyst. Note that the catalyst may be consumed during one of the intermediate steps, but it will be created again before the reaction is completed. Positive and Negative Catalysts (Inhibitors) Usually when someone refers to a catalyst, they mean a positive catalyst, which is a catalyst that  speeds up the rate of a chemical reaction by lowering its activation energy. There are also negative catalysts or inhibitors, which slow the rate of a chemical reaction or make it less likely to occur. Promoters and Catalytic Poisons A promoter is a substance that increases the activity of a catalyst. A catalytic poison is a substance that inactivates a catalyst. Catalysts in Action Enzymes are reaction-specific biological catalysts. They react with a substrate to form an unstable intermediate compound. For example, carbonic anhydrase catalyzes the reaction:H2CO3(aq) ⇆ H2O(l) CO2(aq)The enzyme allows the reaction to reach equilibrium more quickly. In the case of this reaction, the enzyme makes it possible for carbon dioxide to diffuse out of blood and into the lungs so it can be exhaled.Potassium permanganate is a catalyst for the decomposition of hydrogen peroxide into oxygen gas and water. Adding potassium permanganate increases the temperature of the reaction and its rate.Several transition metals can act as catalysts. A good example of platinum in the catalytic converter of an automobile. The catalyst makes it possible to turn toxic carbon monoxide into less toxic carbon dioxide. This is an example of heterogeneous catalysis.A classic example of a reaction that doesnt proceed at an appreciable rate until a catalyst is added is that between hydrogen g as and oxygen gas. If you mix the two gases together, nothing much happens. However, if you add heat from a lighted match or a spark, you overcome the activation energy to get the reaction started. In this reaction, the two gases react to produce water (explosively).H2 O2 ↔ H2O The combustion reaction is similar. For example, when you burn a candle, you overcome the activation energy by applying heat. Once the reaction starts, heat released from the reaction overcomes the activation energy needed to allow it to proceed.