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How To Select A Topic For An Argumentative Essay
Tuesday, August 25, 2020
Why Brands Should Take a Stance on Contentious Issues
An ever increasing number of enterprises are giving it a shot and voicing suppositions on in some cases disagreeable social issues. While some unequivocally accept this isn't a proper domain for organizations, a review by the Global Strategy Group really indicated itââ¬â¢s what most of the open needs â⬠over 56% of the respondents felt that enterprises should take a position on significant issues, regardless of whether theyââ¬â¢re questionable. Be that as it may, this sort of support can be a dangerous move that can possibly rouse kickback, so is it justified, despite all the trouble? I, for one, emphatically accept that the appropriate response is yes. Other than better associating with your clients, organizations can really realize incredible change. Be that as it may, before you become progressively vocal on a specific issue, there are various variables to think about first. Shoppers vote with their wallet Taking an open position on a disputable issue can win you some unwavering clients, however it might likewise cost you others. As indicated by one overview, 45 percent of buyers have prevented buying from an organization since they couldn't help contradicting a position taken by the business. While most of overview respondents demonstrated that they would be bound to purchase from a business they concurred with, just 3 out of 10 have really done as such. Which carries me to my next point. Be certain the reason is pertinent to your clients Before you stand firm on an issue, ensure it fits with your image personality and the estimations of your clients. A genuine model is Rescue Chocolate, a Brooklyn-based creator of vegetarian chocolates that gives their benefits to creature salvage associations. Along these lines, when they stand firm on creature related social issues, for example, enactment including pit bulls, it fits consistently with their image personality. Activities express stronger than words At the point when organizations voice a sentiment on an issue, buyers see them in a progressively positive light when they make a move instead of just issue an announcement. For instance, when McDonaldââ¬â¢s and Starbucks took a situation on the lowest pay permitted by law, 77% of Americans studied thought of it as proper. Disney, then again, showed their position on the issue by raising employeesââ¬â¢ compensation, and 91 percent of individuals esteemed that activity fitting. A few causes are ââ¬Å"saferâ⬠than others Letââ¬â¢s face it â⬠no one is going to blacklist your image for standing firm on a reason, for example, yearning and destitution. Different issues be that as it may, similar to weapon control, same-sex marriage and transgender washrooms, may request a progressively threatening reaction from certain clients. Starbucks accepted the consequences for their open duty to sourcing reasonable exchange espresso, however their position on same-sex marriage prompted the notorious ââ¬Å"Dump Starbucksâ⬠blacklist with an appeal marked by more than 56,000 purchasers. The Bottom Line All in all, should brands take positions on disputable issues? It truly relies upon your business yet I think as a rule, the appropriate response is yes. In any case, continue with alert. Ensure your position fits in with your brandââ¬â¢s personality and your customersââ¬â¢ values. Also, be set up to back up your position and be prepared for backfire. You may estrange a few purchasers who donââ¬â¢t concur with you, however youââ¬â¢ll fortify the association and devotion of the individuals who do.
Saturday, August 22, 2020
Path of the Stars Essay Example for Free
Way of the Stars Essay The tune ââ¬Å"Starsâ⬠from the musicale Les Miserables is sung by Inspector Javert close to the finish of Act I when he understood that it was Jean Valjean whom he had helped escape from the gathering of Thenardier. Investigator Javert is a fairly inquisitive character. A decent portrayal of him is very much spread out in the novel. In any case, in the musicale form, just scraps of Javertââ¬â¢s character can be sparkled when watched cautiously. ââ¬Å"Starsâ⬠may not be one of the universally prestigious tunes from musicale like ââ¬Å"I Dreamed a Dreamâ⬠and ââ¬Å"On My Ownâ⬠, however it offers a decent understanding into the way Inspector Javert considers himself to be a law-implementation specialist, criminals like Jean Valjean, and his fixation, verging on franticness, in the quest for culprits, particularly Jean Valjean, to confront equity. Javertââ¬â¢s considers himself to be one of the stars, ââ¬Å"filling the haziness with request and light â⬠¦sentinels, quiet and sure, keeping watch in the night. â⬠He considers himself to be an unpretentious individual in the public eye maintaining the control and remaining as a vanguard of harmony consistently on the watch. He is consistently there to keep up the harmony in the public eye. He accepts that every one of us, similar to the stars, knows his legitimate spot and capacity in the public arena and the individuals who stray from their fixed and sure ways, offenders and escapees, ââ¬Å"must pay the priceâ⬠and face equity. Crooks are stars that have lost their direction, men who have veered off from their jobs in the public arena. They escape in obscurity for they are out of graces according to God, as indicated by Javert. As a sacrosanct obligation, Javert has brought it into himself, depending on the stars, that he would not rest until these outlaws are brought to confront equity. This obligation is his job in the public eye; his course and point in the skies as one of the stars, ââ¬Å"and so it must be, for so it is composed. â⬠If we follow Javertââ¬â¢s theory that all men in the public arena are nevertheless stars with fixed way in the skies and those stars that tumble from their ways ââ¬Å"fall in flame,â⬠this equivalent way of thinking gives us a thought of how hard Javert could be even to himself. On the off chance that and when Javert, as a star in the sky, veers off from his fixed way he, also, must follow through on the cost. This knowledge into the considering Javertââ¬â¢s gives as a dim premonition of what may occur on the off chance that he bombs in his quest for Jean Valjean (as the case would be in Act II). Javert may not be one of the most agreeable characters in the musicale Les Miserables yet he gives us a decent image of a portion of our general public today. Individuals who will in general be over the top and unbending in their perspectives are encapsulated by Javert. I am not a decent position to condemn individuals like Javert. To certain degrees I concur with Javert that every one of us has a job in the public eye and when we vacillate we should pay dearly. Be that as it may, I don't concur in the inflexible use of equity as embraced by Javert. I accept that when an individual submits an off-base we should temper our judgment by hearing out the reasons of the guilty party, expecting great naturedly that he submitted such offense accidentally. I have confidence in equity with sympathy. Equity, all things considered, has consistently been delineated as a woman blindfolded so she may hear and weight with her heart the contentions laid before her.
Sunday, July 26, 2020
Dysthymia in Children as a Depressive Disorder
Dysthymia in Children as a Depressive Disorder GAD Treatment Print Dysthymia in Children as a Depressive Disorder By Lauren DiMaria linkedin Lauren DiMaria is a member of the Society of Clinical Research Associates and childhood psychology expert. Learn about our editorial policy Lauren DiMaria Medically reviewed by Medically reviewed by Steven Gans, MD on August 05, 2016 Steven Gans, MD is board-certified in psychiatry and is an active supervisor, teacher, and mentor at Massachusetts General Hospital. Learn about our Medical Review Board Steven Gans, MD Updated on February 24, 2020 Depression Overview Types Symptoms Causes & Risk Factors Diagnosis Treatment Coping ADA & Your Rights Depression in Kids JPCreative / Getty Images Dysthymia, also known as dysthymic disorder or DD, is a milder but chronic depressive disorder that is sometimes seen in children. The Course of Dysthymia Like other depressive disorders, the course of dysthymia varies in children. While the DSM-IV criteria require a child to experience symptoms for at least one year to be diagnosed with dysthymia, the median dysthymic episode for children is 3.9 years. Approximately 3 percent of children meet the criteria for dysthymia. However, some researchers argue that an even higher percentage of children have DD. The chronic nature of dysthymia makes it easy for parents to mistakenly attribute the symptoms to a childs personality. Children with DD may not complain of feeling depressed or sad because they do not recognize their mood as being different from what they normally feel. Symptoms Symptoms of DD are similar to those of major depressive disorder, but are less severe and are less likely to impair daily functioning. Symptoms of Dysthymic Disorder in Children Depressed moodSadnessFeelings of hopelessness and/or worthlessnessWithdrawal from friends and familyLow self-esteemEating or sleeping pattern changesUnexplained physical ailmentsLack of concentrationThoughts or action of self-harm or suicideInability to experience pleasure or joyIrritabilityRestlessness or fatigue Despite the milder symptoms of dysthymia, it is still thought that its chronic nature may interfere with a childs development of interpersonal relationships, positive self-esteem, and problem-solving skills. Signs Your Child Is Depressed Recovery and Double Depression Recovery for children with dysthymia is likely. However, the majority of children will have another dysthymic episode in the future. Approximately 75 percent of children who experience a dysthymic episode will also experience a major depressive episode, a shorter but more severe depressive disorder. When a child who has dysthymia experiences a major depressive episode, the combination is called double depression. Factors that may increase a childs likelihood of developing double depression were identified by Dr. Daniel Klein and colleagues in a 10-year follow-up of children with dysthymia. Identified risk factors were: First dysthymic episode at a young ageCo-existing anxiety disorderStrong family history of major depressive disorderPoor early relationship with motherHistory of sexual abuseUnderlying personality disorder It has been noted that children with double depression may have shorter episodes of major depressive disorder. According to Dr. Kovacs and colleagues, this is because it is easier for a child to return to a baseline mood of dysthymia, or mild depressive symptoms, than a baseline with no presence of depressive symptoms. Nonetheless, all depressive disorders require treatment in children. What Parents Should Know About Childhood Depression Seeking Help Like other depressive disorders, dysthymic disorder is associated with serious short- and long-term consequences, such as poor academic and social performance, substance abuse, and increased risk of suicide. Of course, not all children with dysthymia will experience negative outcomes, but given the association, treatment is recommended. Treatment options for children with dysthymia are typically psychotherapy, medication, or a combination approach. Be sure to talk to your childs pediatrician or other mental health providers if she has symptoms of dysthymia or another depressive disorder. Depressive disorders should never be left untreated in children. The Consequences of Untreated Childhood Depression
Friday, May 22, 2020
Foreign Exchange Policy at Gm Essay - 723 Words
Your write-up should be eight to ten pages (double-spaced). If you provide information outside the case or the textbook, use a footnote to indicate the source. You can use pictures, but no more than four, and each figure should be no more than half a page in size. 1. Hedging Policies at GM. Describe GMââ¬â¢s corporate hedging policies. What are the objectives of GMââ¬â¢s FX risk management policies? What are GMââ¬â¢s passive policies to hedge operating exposures? Use the numbers provided in the case on Canadian dollars to illustrate (you have to change the numbers on pages 4 and 5 from euro to Canadian dollar and follow the same logic). 2. Transaction Exposures vs. Translation Exposures. Define transaction exposures and translation exposures. Whatâ⬠¦show more contentâ⬠¦On the other hand, the cost of hedging was very high (see Exhibit 13). For example, the estimated cost of hedging a $300m exposure using 12-month forward contracts was $40.3m. Based on the cost/benefit analysis, do you think GM should hedge its ARS exposure? Why or why not? What are other ways GM can mitigate the impact of a likely ARS devaluation (you should probably rule out using other ARS derivatives other than forward contracts because those derivatives may not exist)? Hint: look for answers in the lecture notes and the textbook for other ways to mitigate exposure. For case 3 writeup and presentation, you need to quantify everything and the following serves as a check list. A: What is the net amount of transactional exposure in CAD for GM? B: On the date of the memo, the value of CAD is 1.578CAD/US$, what is the amount GM has to pay in part A in terms of US$? C: After twelve months, assume that CAD appreciates to 1.529CAD/US$, what is the amount GM has to pay in part A in terms of US$ if GM does not hedge at all? What is the loss for GM (HINT: compare the numbers in parts B and C)? D: After twelve months, assume that CAD appreciates to 1.529CAD/US$, what is the amount GM has to pay in part A in terms of US$ if GM uses the passive 50% hedging policy? What is the loss for GM (HINT: compare the numbers in parts B and D)? E: After twelve months, assume that CAD appreciates to 1.529CAD/US$, what is the amount GM has toShow MoreRelatedGm Hedging Strategies Yen1166 Words à |à 5 Pages| Foreign exchange hedging strategies at General Motors | Competitive exposures | Project on International FinanceMar 2011 | ------------------------------------------------- Overview of General Motors and its corporate hedging policy General Motors was the worldââ¬â¢s largest automaker and since 1931, the worldââ¬â¢s sales leader. In 2000, it had a net income of $4.4 billion on revenues of $184.6 billion. North America represented the majority of sales to end customers but international operationsRead MoreCase Study : Problem And Key Issues1367 Words à |à 6 PagesAnthony Rivard. case. MBA 676 Problem / Key Issues. What is the main problem to be solved? How should GM develop their strategy in China to respond to the uncertainties in the business environment? What are the key issues (sub-problems) that need to be analyzed in order to solve the main problem? 1. How competition is expanding and strategizing both foreign and domestically. 2. How will potential Govââ¬â¢t restrictions affect the auto market in China? 3. How do other regional and strategic opportunitiesRead MoreEssay about General Motors Risk Management Policy975 Words à |à 4 PagesWhat was the stated objective of General Motors Risk Management policy? Three primary objectives: 1) Reduce cash flow and earnings volatility ââ¬â this means management hedges the companyââ¬â¢s transaction exposures and deliberately pays no attention to any balance sheet exposures or translation exposures. 2) Minimize the management time and costs dedicated to global FX management ââ¬â this is as a result of an internal study that determined that the investment of resources in active FX managementRead MoreForeign Exchange Hedging Strategy at General Motors Transactional and Translational Exposures2041 Words à |à 9 PagesForeign Exchange Hedging Strategies at General Motors: Transactional and Translational Exposure Problem Statement In September of 2001 General Motors (GM) was faced with a billion dollar exposure to the Canadian dollar. At the time, North America represented approximately three-quarters of GMââ¬â¢s total sales and this large exposure to the CAD could significantly affect GMââ¬â¢s financial results. GM had a passive strategy of hedging 50% of its exposure; this paper explores the impact of hedgingRead MoreHedging at General Motors Essay3612 Words à |à 15 PagesMotors (GM) undertakes its manufacturing operations in over 30 countries with vehicles being sold in over 200 countries. Through undertaking its international operations it also subjects itself to various types of foreign exchange exposures due to fluctuations in the values of currencies; to manage this problem it has adopted a passive hedging policy and aims to reduce the impact of foreign exchange exposures on the business. The first part of this report outlines the various types of foreign exchangeRead MoreForeign Exchange Hedging Strategy at General Motors Transactional and Translational Exposures2047 Words à |à 9 PagesForeign Exchange Hedging Strategies at General Motors: Transactional and Translational Exposure Problem Statement In September of 2001 General Motors (GM) was faced with a billion dollar exposure to the Canadian dollar. At the time, North America represented approximately three-quarters of GMââ¬â¢s total sales and this large exposure to the CAD could significantly affect GMââ¬â¢s financial results. GM had a passive strategy of hedging 50% of its exposure; this paper explores the impact ofRead MoreEssay about Thailandà ´s International Trade Policy1368 Words à |à 6 Pagesis the primary goal of Thailandââ¬â¢s international trade policy. The Association of Southeast Asian Nations (ASEAN) Economic Community (AEC) was established as an effective cooperative strategy for gaining market advantages through regional market integration. Thailand aims to capitalize on trade agreements by networking and entering partnership with neighboring countries. Currently, Thailandââ¬â¢s cross-border trade in the Greater Mekong Subregion (GMS) plays a crucial role in globalization, because it facil itatesRead MoreForeign Exchange Hedging Strategies at General Motors: Transactional and Translational Exposures2336 Words à |à 10 PagesIntroduction General Motors was the worldââ¬â¢s largest automaker and, since 1931, the worldââ¬â¢s sales leader. In 2001, GM had unit sales of 8.5 million vehicles and a 15.1% worldwide market share. Founded in 1908, GM had manufacturing operations in more than 30 countries, and its vehicles were sold in approximately 200 countries. In 2000, it generated earnings of $4.4 billion on sales of $184.6 billion. The company is trying to accurately calculate the risk of a potential devaluation to the ARS. InRead MoreAccounting Reporting Criteria (Gm and Toyota) Essay examples1273 Words à |à 6 PagesAccounting Reporting Criteria (GM and Toyota) Team B Megan Wooliver September 7, 2010 Accounting Reporting Criteria In order to keep up with the times most organizations of today are finding themselves consistently coming up with different ways to keep accounting information personal as well as accurate. Providing good accounting information not only leads to better decisions but also increase in profit. Even two different organizations that provide a similar product or service haveRead MorePest Analysis Of General Motors In China1287 Words à |à 6 PagesGeneral Motors (GM) has been participating in the Chinese automotive industry for over nine decades. In ensuring, that General Motorââ¬â¢s operations in China remains competitive as well as achieving their vision to be the most valued car marker in the Chinese auto market, as such a PEST analysis is to analyse the automotive market environment in China. The analyses will assist General Motor in understanding current and future implication on the business and automotive market environment in China that
Friday, May 8, 2020
Case Study Of Garmin Uses Technology Help Promote...
The sum of many is always greater than the sum of one. Utilizing group think can position the company with a unique innovative idea. Currently Garmin uses technology to help promote collaboration between departments and also offices. There are multiple telecommunication technologies that allow for this to happen. At Garmin we currently utilize virtual teams in order to come together and accomplish multiple goals. These teams are designed in order to save the company on travel costs by giving the ability to work remotely via web meetings or conference calls. Garmin has done a great job of promoting these teams with video conferencing so that you get an understanding of who you are working with. Opportunities for Garmin in order toâ⬠¦show more contentâ⬠¦At this point in my experience with Garmin I would not have any additional recommendations for the company to improve upon it research and development area. With the advancement of technology in the work place many analog tasks have been converted to technology which is aiding the advancement. Through almost all departments of the business technology has emerged as the key factor in future growth. I believe that throughout the proposal my suggestions will aid in the growth of the company in the following ways. Throughout this proposal I have put more ideas on the table. This effort is better than a group of like-minded individuals. I also included varied perspectives from different departments and segments of the business. By including employees, managers, shareholders and customers I have been able to give a clearer picture of the context and potential pitfalls. Working with multiple levels of the organization my proposal gains buy-in support from the primary stakeholders. These primary stakeholders have a lot to gain from increasing the technology impact with the business. In the proposal for streamlining the technology suite for customer service, sales and marketing I believe that this would be fair for everyone. Meaning that he ends result would affect them all the same, giving each respective team more access and nimbleness to share information internally and externally. Within this proposal IShow MoreRelatedConsumer Lifestyle in Singapore35714 Words à |à 143 Pages............................ 28 Male Grooming ....................................................................................................................... 29 à © Euromonitor International CONSUMER LIFESTYLES IN SINGAPORE Passport II Use of Hair Care Salons, Spas, Nail and Beauty Parlours ..................................................... 30 Chart 11 Chart 12 Value Sales of Beauty and Personal Care Key Categories 2006-2011 ...... 31 Regional Ranking of Per Capita Sales of Mens Grooming
Wednesday, May 6, 2020
Does Technology Corrupt Society Free Essays
Does technology corrupt society? (By: Gordon Turtle) Does technology corrupt society? Thatââ¬â¢s a commonly asked question. If you think about it, technology helps society more then it harms it. A lot of schools disallow the use of cell phones or laptops unless they are used for school it-self. We will write a custom essay sample on Does Technology Corrupt Society or any similar topic only for you Order Now How would students communicate without them? Through the one hour to an hour and forty five minutes of lunch? What about technology used for medical purposes. Also, technology used for electronics such as computers, lights, etcâ⬠¦ Lastly, technology used for communication, like cell phones, radios, etcâ⬠¦ We use technology almost everywhere; we use it for medical to help people get rid of diseases and injuries. It also helps doctors train better, easier, and more efficiently. If we didnââ¬â¢t have technology then we would still be cavemen living in caves with no light, no way of surviving injuries or illnesses. If we didnââ¬â¢t have any medical abilities the human race would have went extinct a long time ago. Technology gave us electricity and electronics. Without technology we wouldnââ¬â¢t have t. v. ââ¬â¢s, toyââ¬â¢s, game systems, etcâ⬠¦ If man evolved without technology then we wouldnââ¬â¢t have come this far, we wouldnââ¬â¢t be as smart as we are now. We also wouldnââ¬â¢t have any way of teaching our children or other kids about how to live life or how to be good responsible adults. Technology also gave us communication devices such as the cellphone, house phone, computers, laptops, etcâ⬠¦ If we didnââ¬â¢t have technology the military would have fast ways of communicating with its soldiers. Without communication we could think we are the only country on earth for all we knew. Communication devices gave us the power to talk to one another from one side of the earth to the other in seconds. Imagine a world without communication. Imagine you had to write a letter and have it read days or even months later, and then having to wait days or months for a response. Communication devices are one of the most important pieces of technology ever made. Without them we might as well go live in a cave with the few people we know, thinking that you were the only ones that are on the earth. Thatââ¬â¢s why technology doesnââ¬â¢t corrupt society, and that technology is what brought us to where we are today. If you think about it, technology helps society more then it harms it. How to cite Does Technology Corrupt Society, Essays
Tuesday, April 28, 2020
Sodium Thiosulfate Reaction free essay sample
Concepts â⬠¢ Kinetics â⬠¢ Order of reaction â⬠¢ Rate law â⬠¢ Concentration Materials Hydrochloric acid solution, HCl, 2 M, 25 mL Sodium thiosulfate solution, Na2S2O3, 0. 15 M, 150 mL Distilled or deionized water Beakers, 100-mL, 5 Graduated cylinders, 50- or 100-mL, 2 Graduated cylinders, 10-mL, 5 Overhead projector or light box Permanent marker Stirring rods Stopwatch or timer Safety Precautions Hydrochloric acid solution is corrosive to eyes and skin. It is moderately toxic by ingestion and inhalation. Sodium thiosulfate solution is a body tissue irritant. The reaction of sodium thiosulfate and hydrochloric acid generates sulfur dioxide gas, which is a skin and eye irritant. Perform this demonstration in a well-ventilated lab only. Avoid contact of all chemicals with eyes and skin. Wear chemical splash goggles, temperature-resistant gloves, and chemical-resistant apron. Please review current Material Safety Data Sheets for additional safety, handling, and disposal information. Procedure 1. Label five 100-mL beakers 1ââ¬â5 and clean the bottom of each beaker. We will write a custom essay sample on Sodium Thiosulfate Reaction or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page 2. Draw a large ââ¬Å"Xâ⬠across the bottom on the outside of each beaker. Place the beakers on an overhead projector stage or a light box so that students can view the ââ¬Å"X. â⬠3. Using separate graduated cylinders for the solution and water, measure and add the required amounts of 0. 15 M sodium thiosulfate and distilled water to each beaker. Be as precise as possible. Beaker 0. 15 M Na2S2O3 Distilled Water 1 50. 0 mL 0 mL 2 40. 0 mL 10. 0 mL 3 30. 0 mL 20. 0 mL 4 20. 0 mL 30. 0 mL 5 10. 0 mL 40. 0 mL 4. Have students calculate the final concentration of sodium thiosulfate in each beaker 1ââ¬â5. 91860 011509 Flinn Scientificââ¬âTeaching Chemistry eLearning Video Series 5. Record the following information in a data table: Beaker, volume of Na2S2O3 solution, volume of distilled water, concentration of Na2S2O3, reaction time (sec), and 1/reaction time (reaction rate). See the Sample Data and Results table in the Discussion section. 6. Measure 5. 0 mL of 2 M hydrochloric acid into each of five 10-mL graduated cylinders. 7. Starting with beaker #1, carefully add the HCl all in one pour to the sodium thiosulfate solution. Stir the solution once with a stirring rod and immediately start timing. 8. Stop timing when the black ââ¬Å"Xâ⬠is no longer visible. Record the reaction time in seconds in the data table. . Repeat steps 7 and 8 with beakers 2ââ¬â5. 10. Calculate 1/reaction time for each trial. Plot concentration vs. time and concentration vs. 1/time on separate graphs. Disposal Please consult your current Flinn Scientific Catalog/Reference Manual for general guidelines and specific procedures governing the disposal of laboratory waste. Collect the leftover reaction mixtures and filter to separate the solid sulfur product. The sulfur may be disposed of in a landfill according to Flinn Suggested Disposal Method #26a. The filtrate may be neutralized and disposed of down the drain with excess water according to Flinn Suggested Disposal Method #26b. Tips â⬠¢ This activity may be performed as a chemical demonstration with classroom participation or as a student activity. The contents of the beakers project well on an overhead projector and the time to the disappearance of the black ââ¬Å"Xâ⬠is easily seen and measured. â⬠¢ The reaction may be downsized for a student lab activity. Carry out individual trials in separate wells in a 6-well reaction plate or in small medicine cups. If students will be doing the experiment in the lab, it is a good idea for them to start with beaker #5, because it takes the longest time. The activity may also be performed as a cooperative class exercise with different groups investigating different variables, including the effect of HCl concentration and the effect of temperature. The reaction rate is zero-order with respect to HCl. â⬠¢ Empty the beakers and clean them thoroughly using paper towels to remove the sulfur. If the colloidal sulfur is allowed to sit in the beakers for an extended time, it will be much more difficult to remove the deposits from the glass. â⬠¢ To achieve better mixing of the reactants, add the hydrochloric acid using a 10-mL luer-lock plastic syringe (without needle). Squirt the acid using a fair amount of force. â⬠¢ When lower concentrations of sodium thiosulfate are used, the rate law does not appear to be as simple as predicted in this experiment. At lower concentrations, the reaction appears to be closer to 3/2-order in sodium thiosulfate and 1/2-order in hydrochloric acid. The reaction time is more difficult to measure at lower concentrations because the onset of turbidity is more gradual. â⬠¢ Both the overall chemical equation and the mechanism for the decomposition of sodium thiosulfate are more complex than suggested by Equation 1. The reaction is acid-catalyzed, which means that the acid concentration must have some bearing on the rate in terms of producing an equilibrium concentration of HS2O3ââ¬â ions, The HS2O3ââ¬â ion is a reactive intermediate, reacting further with additional S2O32ââ¬â ions to produce polymeric ions containing multiple S atoms. When the chain of S atoms in a polymeric ion becomes long enough, it ââ¬Å"closesâ⬠in on itself to form a ring of elemental sulfur (S8). ââ¬â ââ¬â S2O32ââ¬â + H+ lt; ââ¬â gt; HS2O3 ââ¬âââ¬â ââ¬â Hââ¬âSââ¬âSO3ââ¬â + nS2O32ââ¬â Hââ¬âSââ¬â(S)nââ¬âSO3 + nSO32ââ¬â ââ¬â ââ¬â ââ¬â ââ¬â Hââ¬âSââ¬âSnââ¬âSO3 lt; ââ¬â gt; H+ + Sââ¬âSnââ¬âSO3 ââ¬âââ¬â ââ¬â Sââ¬âS7ââ¬âSO3 S8 + SO32ââ¬â ââ¬â2ââ¬â à © 2009 Flinn Scientific, Inc. All Rights Reserved. 91860 Discussion Sodium thiosulfate reacts with hydrochloric acid to form sulfu r and sulfur dioxide (Equation 1). Na2S2O3(aq) + 2HCl(aq) S(s) + SO2(g) + 2NaCl(aq) Equation 1 The kinetics of the reaction can be analyzed by graphing the concentration of Na2S2O3 as a function of both reaction time and 1/time. A plot of concentration versus time gives a curved line, which levels off as it approaches the x-axisââ¬âthe reaction slows down as the reactant concentration decreases. The rate of a reaction is inversely proportional to reaction time. A plot of concentration of versus 1/time gives a straight line. The rate is directly proportional to concentration, and the reaction appears to be first order with respect to sodium thiosulfate concentration. Sample Data and Results Beaker 1 2 3 4 5 Volume of Na2S2O3 (mL) 50 40 30 20 10 Volume of H2O (mL) 0 10 20 30 40 [Na2S2O3], M 0. 15 0. 12 0. 090 0. 060 0. 030 Reaction time (sec) 22. 5 27. 3 35. 1 60. 0 159. 1 Reaction rate (1/time, secââ¬â1) . 0444 . 0367 . 0285 . 0167 . 00629 180 160 140 120 100 80 60 40 20 0 0. 00 Effect of concentration on reaction time 0. 05 0. 10 0. 15 0. 20 Na 2 S2 O3 Concentration, M 0. 07 0. 6 0. 05 0. 04 0. 03 0. 02 0. 01 0 0. 00 Effect of concentration on reaction rate 0. 05 Na 2 S2 O3 Concentration, M 0. 10 0. 15 0. 20 ââ¬â3ââ¬â à © 2009 Flinn Scientific, Inc. All Rights Reserved. 91860 Connecting to the National Standards This laboratory activity relates to the following National Science Education Standards (1996): Unifying Concepts and Processes: Grades Kââ¬â12 Evidence, models, and explanation Constancy, change, and measurement Content Standards: Grades 9ââ¬â12 Content Standard A: Science as Inquiry Content Standard B: Physical Science, structure and properties of matter, chemical reactions, motions and forces Flinn Scientificââ¬âTeaching Chemistryâ⠢ eLearning Video Series A video of the Rate of Reaction of Sodium Thiosulfate and Hydrochloric Acid activity, presented by Annis Hapkiewicz, is available in Rate Laws, part of the Flinn Scientificââ¬âTeaching Chemistry eLearning Video Series. Materials for Rate of Reaction of Sodium Thiosulfate and Hydrochloric Acid are available from Flinn Scientific, Inc. Materials required to perform this activity are available in the Reaction Order and Rate Lawsââ¬âStudent Laboratory Kit available from Flinn Scientific. Materials may also be purchased separately. Catalog No. Description AP4864 H0034 S0114 AP1572 GP1010 GP2005 GP2015 Reaction Order and Rate Lawsââ¬âStudent Laboratory Kit Hydrochloric Acid, 3 M, 500 mL Sodium Thiosulfate Pentahydrate, Reagent, 500 g Timer, Stopwatch, Flinn Beaker, Borosilicate Glass, 100 mL Graduated Cylinder, Borosilicate Glass, 10-mL Graduated Cylinder, Borosilicate Glass, 50-mL Consult your Flinn Scientific Catalog/Reference Manual for current prices. ââ¬â4ââ¬â à © 2009 Flinn Scientific, Inc. All Rights Reserved. 91860
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