Arrhenius Equation Formula and Example

In 1889, Svante Arrhenius formulated the Arrhenius equation, which relates reaction rate to temperature. A broad generalization of the Arrhenius equation is to say the reaction rate for many chemical reactions doubles for every increase in 10 degrees Celsius or Kelvin. While this rule of thumb isnt always accurate, keeping it in mind is a good way to check whether a calculation made using the Arrhenius equation is reasonable. Formula There are two common forms of the Arrhenius equation. Which one you use depends on whether you have an activation energy in terms of energy per mole (as in chemistry) or energy per molecule (more common in physics). The equations are essentially the same, but the units are different. The Arrhenius equation as its used in chemistry is often stated according to the formula: k Ae-Ea/(RT) k is the rate constantA is an exponential factor that is a constant for a given chemical reaction, relating the frequency of collisions of particlesEa is the activation energy of the reaction (usually given in Joules per mole or J/mol)R is the universal gas constantT is the absolute temperature (in Kelvins) In physics, the more common form of the equation is: k Ae-Ea/(KBT) k, A, and T are the same as beforeEa is the activation energy of the chemical reaction in JouleskB is the Boltzmann constant In both forms of the equation, the units of A are the same as those of the rate constant. The units vary according to the order of the reaction. In a first-order reaction, A has units of per second (s-1), so it may also be called the frequency factor. The constant k is the number of collisions between particles that produce a reaction per second, while A is the number of collisions per second (which may or may not result in a reaction) that are in the proper orientation for a reaction to occur. For most calculations, the temperature change is small enough that the activation energy is not dependent on temperature. In other words, its usually not necessary to know the activation energy to compare the effect of temperature on reaction rate. This makes the math much simpler. From examining the equation, it should be apparent the rate of a chemical reaction may be increased by either increasing the temperature of a reaction or by decreasing its activation energy. This is why catalysts speed up reactions! Example Find the rate coefficient at 273 K for the decomposition of nitrogen dioxide, which has the reaction: 2NO2(g) → 2NO(g) O2(g) You are given that the activation energy of the reaction is 111 kJ/mol, the rate coefficient is 1.0 x 10-10 s-1, and the value of R is 8.314 x 10-3 kJ mol-1K-1. In order to solve the problem, you need to assume A and Ea dont vary significantly with temperature. (A small deviation might be mentioned in an error analysis, if you are asked to identify sources of error.) With these assumptions, you can calculation the value of A at 300 K. Once you have A, you can plug it into the equation to solve for k at the temperature of 273 K. Start by setting up the initial calculation: k Ae-Ea/RT 1.0 x 10-10 s-1 Ae(-111 kJ/mol)/(8.314 x 10-3 kJ mol-1K-1)(300K) Use your scientific calculator to solve for A and then plug in the value for the new temperature. To check your work, notice the temperature decreased by nearly 20 degrees, so the reaction should only be about a fourth as fast (decreased by about half for every 10 degrees). Avoiding Mistakes in Calculations The most common errors made in performing calculations are using constant that have different units from each other and forgetting to convert Celsius (or Fahrenheit) temperature to Kelvin. Its also a good idea to keep the number of significant digits in mind when reporting answers. Arrhenius Plot Taking the natural logarithm of the Arrhenius equation and rearranging the terms yields an equation that has the same form as the equation of a straight line (y mxb): ln(k) -Ea/R (1/T) ln(A) In this case, the x of the line equation is the reciprocal of absolute temperature (1/T). So, when data is taken on the rate of a chemical reaction, a plot of ln(k) versus 1/T produces a straight line. The gradient or slope of the line and its intercept can be used to determine the exponential factor A and the activation energy Ea. This is a common experiment when studying chemical kinetics.

Essay about The Hero Monomyth in Sons of Anarchy - 665 Words

Claire Stemmer 16 March 2015 HUM 115-502 Prof. Streit SWA 4: Patterns of the Hero Monomyth in Sons of Anarchy In his renowned work, The Hero with a Thousand Faces, Joseph Campbell defined the essential stages of the Heroic Journey, using examples from a wide range of myths and stories. His objective was not only to establish the framework for hero tales, but also to convey why these elements of the monomyth prevail in so many different works. Campbell’s view states that â€Å"the hero myth is really written about every human being: we are all heroes struggling to accomplish our adventure† (Whomsley, 185). From this perspective, it seems justified that these patterns continue to appear in so many stories adventure and heroism; we all want our†¦show more content†¦The element of the Hero’s Journey that the show most clearly reflects is the concept of â€Å"Atonement with the Father†. Central to the plotline is the relationship between father and son, and the implications are manifold. Clay Morrow fills the role of the mythical father figure, as well as one of the show’s antagonists despite his actual familial relationship with Jax. In Campbell’s analysis of the Hero’s Journey, the father figure plays a huge part in the hero’s transformation process: â€Å"His role is to test the hero to ascertain his worthiness† (190). The Father can also symbolize the source of evil that the hero must eliminate: â€Å"The hero’s quest, if successful, incorporates the defeat of an ogre or villain who represents the fearsome aspect of the father† (190). The point in the series where Jax ends Clay’s life is a truly pivotal moment in his heroic journey, as it signifies our protagonist stepping into a new position of leadership and responsibility. In The Hero with a Thousand Faces, Joseph Campbell delineated the essential features found in myths and stories of heroes and heroic journeys. His purpose in doing so was partly to elucidate the notion that we are all heroes on the course of our own adventures. Looking at contemporary works of fiction through the lens of the heroic monomyth, we are able to make connections between our own heroes and ourselves. Jax

What is Ethnobotany Free Essays

Introduction Plants have long been used in traditional medicine. They have been known as rich sources of modern medicines, drugs and drug products because they produce a host of bioactive molecules, which serve as chemical defenses against predation or infection. By the mid-1980s, most pharmaceutical manufacturers had abandoned exploring folk practices including plant derivatives in their search for new drugs because of the discovery of microorganisms and fungi including the advances of synthetic chemistry in the production of medicines and antibiotics. We will write a custom essay sample on What is Ethnobotany or any similar topic only for you Order Now However, to date, the pendulum is beginning to swing back towards the appreciation of plants used in traditional medicine that has potential novel therapeutic agents. The World Health Organization (WHO) reported that 65-80% of the world’s population mostly in developing countries; widely depend on plants for primary healthcare due to poverty and lack of access to modern medicine [1]. Several ethnobotany studies support this report. [2, 3, 4, 5]. Ethnobotany is the study of the interaction between plants and people in their local environment [5, 6] The ethnobotanical approach is actually one of the several methods in choosing plants for pharmacological studies. There are about less than 0.5% of the estimated 265,000 flowering species on earth which have been studied exhaustively for their chemical composition and medicinal value. Ethnobotany studies of medicinal plants have been used in various ways such as to test hypothesis of use and knowledge, describing the use of plants in a given community or listing plants for food, therapeutic and other ethnobotanical purposes[7]. Herbal medicines that have been based on traditional knowledge are estimated at about 60 billion US dollars in the world market today. Traditional medicine has always been recognized as an important tool for the development of novelties in drug discovery [8]. Traditional medicinal practices through indigenous knowledge are common among tribes and local folks as their primary health care system [9, 10, 11, and 12]. Hence, traditional knowledge of medicinal plants as known by indigenous healers and local folks are not only useful for conservation of cultural tradition and biodiversity but also for community health care and drug development. In this study, medicinal plants refer to traditional medicinal plants used to maintain health and treat illnesses, which are used for more than a generation by the informants or may have the knowledge passed to them through time by their ancestors. There were initiatives to explore the biodiversity of Mt. Arayat. Bagunu et al. [13] documented in their unpublished terminal report 77 species of vascular plants in the northwestern slope of Mt. Arayat; 7 species of the Grass Family, 16 families of forest trees, 9 Orchid families, 18 fern species and 75 mushroom species. Follow up researches were undertaken for more detailed identification of plants available in Mt. Arayat covering important aspects of their potentials for health, medicines and food sources. Abille [14] in her inventory of BS Biology researches of natural products-related from 2001 to 2015 found that phytochemical studies had the highest percentage, followed by antimicrobial (anti-bacterial and anti-fungi) studies and cytotoxicity studies the least. Anent to these studies are the revelations of folk healers that they use some of these plants for treating illnesses and diseases as mentioned in an unpublished report of Espiritu[15] where 55 medicinal plants were identified specifically of their medicinal contributions based on local names. However, the quantitative analysis of the data was a bit explored. Ong and Kim[16] mentioned only one conducted quantitative ethnobotany study by Abe and Ohtani in 2012 in the Philippines in his review of related literature and none so far in Central Luzon. Hence, this study serves as springboard for the understanding of the relative cultural importance of these medicinal plant studied in Mt. Arayat, Pampanga, Philippines and thus support communities to manage their resources more effeftively or finding plants that maybe useful to the community for medical or other purposes. Consistent with R ; D priorities of the agenda thrust of the Department of Science and Technology (DOST) for 2011-2016 to address the identified pressing health problems of the Filipino people by the Department of Health (DOH), the study is aligned with the National Unified Health Research Agenda (NUHRA) towards drug discovery from natural and indigenous sources through ethnobotany. Thus, the documentation of the traditional uses of plants particularly for medicinal value is an urgent matter for preserving the knowledge and providing baseline data for future pharmacological and phytochemical studies and natural product development, which are valuable in healthcare. How to cite What is Ethnobotany, Papers

Relationship Between Ecstasy And Memory Essays -

Relationship Between Ecstasy And Memory Can there be a Relationship between Ecstasy and Memory in the Human Body? Target Article: Parrott, A.C & Lasky, J. (1998) Ecstasy (MDMA) effects upon mood and cognition: before, during and after a Saturday night dance. Psychopharmacology, 139, 261-268. Additional Article: Parrot, A.C., Lees, A., Garnham, N.J., Jones, M., ecstasy: evidence for memory deficits. Journal of Psychopharmacology, 12, 79-83. Rationale and Variables: The Experiment that was conducted in class determined the affects of ecstasy or MDMA on the participants memory. In addition to testing for their ability to recall information it also looked at the number of false memory that were related to the actual word slow in the class study. In the experiment Dr. Earleywine used a list of words that were to be memorized, and recall in a given time. This study is related to another experiment conducted by A.C Parrott and J. Lasky. In their study they looked at the effects of ecstasy or MDMA on mood and cognition. They tested three groups: non- MDMA, novice-MDMA users, and regular MDMA users. They used different methods to test the three groups, included in the methods was word recall, which was also used in the class study by Dr. Earleywine. The result from that experiment showed that ecstasy or MDMA users did have memory problems. Another study was also conducted by A.C. Parrott, A. Leess, N.J Garnham M. Jones, and K. Wesnes, which was relate also to the other experiments. This experiment was conducted using three groups: non-MDMA, novice-MDMA and regular MDMA users. They used series of methods to conduct their study, and found their results similar to the earlier study. Analyzing the finding of the two studies, Dr. Earleywine decided to do a study with the mind set of making a connection between the rates of intrusions that participants who have used MDMA, compared with the rate of intrusions with participants, who did not use MDMA. The independent variables were the two groups MDMA users and non-MDMA users, and the dependent variables are the intrusions, and words recalled. Methods: The data for the experiment was collected form students that were taking psychology at University of Southern California. The participants included 145 women and 92 men. The ethnicity background included Caucasian, African/Caribbean, Asian/Pacific Islander, Latino, Native American, and others, which were not specified. The age of the participants averaged 19.578 years. The procedure of experiment started when Dr. Earleywine distributed the surveys to the participants. In the survey, questions regarding ecstasy and other drugs were asked. The participants were asked to put a check next to statements that were true to them. In the statement the participants were asked if they used MDMA in there life time or if they have never used it. They were also asked their race, age, sex and year in school. When the participants completed the questioner, Dr. Earleywine read a list of 16 words, pausing a few seconds between each word. When he was done reading the list, there was a 30-secon ds period of silence in the lecture room. After the 30-secondes, the participants were asked to recall words that they believed were read and to write them on the back of one of the surveys. Results: The study that was conducted produced results that were not very significant to our predicament. We predicted that the data we would receive would back up the two studies that were conducted, and would also be strong enough to make a statement of its own. But our prediction was far form backing up the two articles that we read. It was stated that 63.7% never used MDMA and 36.3% used MDMA in their lifetime. When the data was analyzed between the two groups, for intrusions and target intrusions they were identical for the most part. The MDMA users in our study were not more likely to make target intrusions. In the recall area of the study, the non-MDMA users recalled an average of 8.8600 words out of 16, and MDMA users averaged 8.1125 words. For the intrusion part of the study the non-MDMA users made 1.0200 intrusions on average and the MDMA users averaged

The Controversy of Keynesian Economics essays

The Controversy of Keynesian Economics essays Two controversial economic policies are Keynesian economics and Supply Side economics. They represent opposite sides of the economic policy spectrum and were introduced at opposite ends of the 20th century, yet still are the most famous for their effects on the economy of the United States when they were used. The founder of Keynesian economic theory was John Maynard Keynes. He made many great accomplishments during his time and probably his greatest was what he did for America in its hour of need. During the 1920's, the U.S. experienced a stock market crash of enormous proportions which crippled the economy for years. Keynes knew that to recover as soon as possible, the government had to intervene and put a decrease on taxes along with an increase in spending. By putting more money into the economy and allowing more Americans to keep what they earned, the economy soon recovered and once again became prosperous. Keynes ideas were very radical at the time, and Keynes was called a socialist in disguise. Keynes was not a socialist, he just wanted to make sure that the people had enough money to invest and help the economy along. As far as stressing extremes, Keynesian economics pushed for a "happy medium" where output and prices are constant, and there is no surplus in supply, but also no deficit. Supply Side economics emphasized the supply of goods and services. Supply Side economics supports higher taxes and less government spending to help economy. Unfortunately, the Supply Side theory was applied in excess during a period in which it was not completely necessary. The Supply Side theory, also known as Reaganomics, was initiated during the Regan administration. During the 1970's, the state and local governments increased sales and excise taxes. These taxes were passed from business to business and finally to the customer, resulting in higher prices. Along with raised taxes for the middle and lower classes, this effect was com...

Smoking in Public Places Should Be Banned

Smoking in Public Places Should Be Banned This article is a kind of sample argumentative essay on the topic Smoking in Public Places Should be Banned Ban the Smoking: It’s Bad for Everyone Second-Hand Smoking Now that America is no longer dependent on tobacco production as a means to sustain its economy, the industry and culture surrounding it should be heavily controlled. Now that fewer people are smoking cigarettes, because of the well-documented health concerns related to its use, more cities and districts are cracking down on smoking in public places – and rightfully so. Smoking in public places should not only be banned, it should come with heavy penalties, such as outlandish fines, criminal charges and, if possible, public beatings. Due to the health problems associated with smoking cigarettes, due to smoking being a fire hazard and offensive to non-smokers, smoking in public places should never go under the radar. It should be banned on a national scale. Smoking cigarettes, cigars or pipes in public places should be banned because it’s offensive to the non-smokers who have to endure the smoke, the butts, the mess and the smell. Consider the typical public place – a market door entrance, a park bench, an elevator. People come to these places for peace and quiet, for necessity, to get to work, so they should not be required to breathe another person’s poisonous tobacco fumes. Everyone knows that second-hand smoke is just as, if not more, dangerous than directly inhaling the smoke. Why should a health-conscious, everyday person have to be penalized for another’s bad decision? It just isn’t right – so smoking in public places should be banned altogether. It’s also disgusting to smell cigarette smoke – even worse when it’s on your clothes. The American government has yet to criminalize the use of all tobacco products, mostly because of billion-dollar companies like Phillip Mor ris, out of Richmond, Virginia, pays millions of dollars in taxes annually. But cigarettes are killing everyday Americans, costing them too much in the long run. They should certainly be banned everywhere, not just in public places. More articles to read:  Junk Food in School  |  Why Are You Not in Class and out There Bleeding? Smoking Is Not Fashionable Anymore! Let’s ban smoking in public places because it gives young, impressionable adolescents the wrong idea. They see it and think it’s a normal, healthy, cool adult thing to do – something they perhaps feel they’re supposed to do it as adults, maybe even as teens. This is bad because they do not possess the foresight and self-preservation experience to avoid doing things that could one day kill them. By banning smoking in public places, fewer people will be seen smoking and, subsequently, outcast from society. It will be the thing that those people do; they will have to hide it. This is good because this mentality will condition smokers to perhaps give up smoking, a good deterrent for sure because the same social and peer pressure that may have encouraged them to begin smoking has gone the other way. Banning smoking in public places is a wonderful idea and should be taken up by every single jurisdiction, municipality, city, hole-in-the-wall town and county in th e country. In addition to smoking raising health concerns, banning public smoking altogether, including indoors, would surely cut down on fires – both in buildings and possibly in nature, as well. Just picture a waiter with five minutes for a smoke standing just outside a restaurant’s kitchen in a rush to fill their nicotine cravings. The headwaiter calls their name and they flick the cancer stick away – it’s not their problem, right? But it’s windy that night and the cigarette rolls into the nearby trash. And, bam – a fire has begun. People could die. How about banning smoking anywhere a fire could start, any place that could endanger others? This would cut down immensely on building fires. Innocent people wouldn’t have to die in fires, and their beloved possessions would not be destroyed. Banning public smoking benefits everyone, including the smoker. Let’s conclude this argument by going a step further. If we can already see how banning public smoking would benefit our citizens – protecting their health, peace of mind, homes and possessions – why stop there? Let’s ban smoking tobacco products altogether! Let’s rid our wonderful society of this evil poison, this killer of people, this addictive substance with no health value whatsoever. Let’s make cigarettes so expensive to buy that few can afford them, and so hard to find that they may as well be sold on the black market. This should apply to those vaporized smoking apparatuses, too. They are said to be a healthier alternative to smoking filter tobacco products, but they are just offensive to be around.

Tarantino's Marketing Case Study Example | Topics and Well Written Essays - 3000 words

Tarantino's Marketing - Case Study Example This set the stage for the meteoric rise of his next film, which was the Oscar winning Pulp Fiction. Tarantino had established a career through the impact these first two projects. In 1994 Reservoir Dogs was voted best film and best debut and in 1995 Pulp Fiction was voted best film and Tarantino best director by Empire magazine1. This seemed to be a new kind of director making new kinds of films which were enormously popular, and which employed extremely good marketing. This dissertation will look in detail at the general marketing and in particular at the posters and other visual media used in these campaigns. It will be focusing on the images, colours and language used and the affect on their audience. In addition, it will be looking also at other visual marketing activities that have been undertaken, for example guerrilla marketing which has used striking posters in unusual locations as well as props scattered around various cities seemingly randomly which made great photos news advertising. It will look at the effect that movie posters have on the film-going public - it seemed that at one time everyone had (or still has) these posters in their rooms. The more controversial side of this medium will also be explored. What techniques are used to create the shock factor and interest in the films that are being advertised How do these techniques actually work, and what implications do they have on other practitioners in the field, and what impact do they have on wider film culture. Finally, the paper will discuss if this style and form of advertising actually has the effect intended. Chapter 1 This chapter will investigate Quentin Tarantino and the types of films that he makes and how this shapes the type of advertising techniques he would use. From this we will then look to investigate the way in which Quentin Tarantino uses shock advertising to grab the attention of the public. Before Tarantino, the general use of posters in advertising forthcoming films, as well as the actual trailers for the films, had been the industry standard method for many years. Eventually as in every design or art medium this dual concept would grow and evolve into a stable model.Tarantino upset this standard set-up by using strikingly original sometimes shocking, single images amongstother marketing and advertising strategies to establish points if difference. Following Tarantino's success, the film advertising industry was not slow to follow his lead using more and more original ideas, using unusual and shocking visual images, to capture the public's imagination. Quentin Tarantino's film Kill Bill had an advertising campaign that illustrates some of these methods. Figure 1 Figure 2 Figure 3 Many different campaigns were designed and they all look different but they all conveyed the same kinds of striking imagery. Also images were used on unusual blank canvases throughout cities, elevator doors for example. This type of advertising added to Quentin Tarantino's reputation as a both as filmmaker and as a general creative person (he also writes scripts). This chapter will therefore concentrate on the effects of the advertising used by Quentin Tarantino and his marketing team. Why have they decided to use a variety of mediums to advertise his films I will attempt to understand how these advertising techn