Tuesday, August 6, 2019
Monday, August 5, 2019
Impacts of Nuclear Energy on Global Business
Impacts of Nuclear Energy on Global Business 1. Background and Overview Tony Blair’s Labour government has finally decided to move ahead â€Å"with a vengeance†(Webster, 2006) with its’ plans for development of nuclear power, ending years of speculation on the issue. Work on the last nuclear power station started eighteen years ago in the UK on Sizewell B and since then there has been a complete embargo on any fresh initiative in the area. Things are now likely to change, much to the concern of environmentalists and anti nuclear campaigners. The use of nuclear power, for any reason, peaceful or otherwise, has always been looked upon with deep suspicion because of its inherent association with weapons of mass destruction and its ability to cause large scale destruction on a horrific and unimaginable scale. â€Å"Many analysts have attempted to explain the visceral hostility toward nuclear power, and the most common explanation is that people link nuclear power with nuclear weapons.†(Lorenzini, 2005) The reasons for this attitude are also justifiable as most scientific work in atomic radiation, atomic change and nuclear fission, be it in the USA, Nazi Germany or communist Russia, at least till 1956, was focussed primarily on the furthering of the atomic bomb. It was only after 1956 that the focus of nuclear technology shifted to the design of safe and reliable nuclear plants. The growth in use of nuclear energy for power entered a state of not just stagnation but moderate decline, world wide, in the late seventies and remained so until the turn of the century and the UK was presumably, but echoing global concern in the formulation of its energy policy. Very few reactors were ordered globally and the new reactors coming on line just about matched requirements. Global capacity increased by only a third in more than a decade. Even then, nuclear energy, from the 442 nuclear power reactors used in 31 countries, adds up to one sixth of the world’s electricity supply today. The growth of nuclear fuel as an energy source has been sluggish due to quite a few reasons, some of which now need rethinking in today’s grim geopolitical and environmental scenario. For more than three decades, energy policies in the United States and much of the Western world have been held in the ideological grip of a flawed concept: the notion that we can achieve sustainable energy by relying solely on conservation and renewable resources, such as wind, the sun, the tides, and organic materials like wood and crop waste. Born in the wake of the 1973 oil embargo and arising out of renewed commitments to environmental quality, this idea has an almost religious appeal. An unintended result is that the world has become ever more reliant on fossil fuels and therefore less able to respond to global warming. (Lorenzini, 2005) It has been the case of the pro nuclear power lobby, for many years now, that nuclear energy is a clean, economic and efficient way to generate power; ideal for continuous generation of medium and large scale electricity. In nuclear power stations, apart from the nuclear reactors, the rest of the equipment works similarly to those in coal or gas fuelled power plants. However, the cheaper and more widely available fuel used by these nuclear plants, compared to those fired by coal, oil and gas, makes the case for its’ wider use attractive. This is especially relevant today with oil hovering in the range of 70 to 73 USD per barrel, and gas from the North Sea wells beginning to run out. With the increase in greenhouse and emission problems and the uncertainty of fossil fuel supplies in a shifting and unstable political environment, the nuclear power option has definitely got itself a strong tailwind. The concerns of the anti nuclear campaigners focus on a number of worrying issues. Their first contention concerns the forecasted reduction of carbon dioxide emission from nuclear power plants; this to them is no more than blatant propaganda. In the US, where much of the worlds uranium is enriched, including Australias, the enrichment facility at Paducah, Kentucky, requires the electrical output of two 1000-megawatt coal-fired plants, which emit large quantities of carbon dioxide, the gas responsible for 50per cent of global warming. Also, this enrichment facility and another at Portsmouth, Ohio, release from leaky pipes 93per cent of the chlorofluorocarbon gas emitted yearly in the US. The production and release of CFC gas is now banned internationally by the Montreal Protocol because it is the main culprit responsible for stratospheric ozone depletion. But CFC is also a global warmer, 10,000 to 20,000 times more potent than carbon dioxide. (Caldicott, 2005) In addition, the environmentalists say that nuclear fuel cycle also consumes large quantities of fossil fuel, in the mining of uranium, in the construction of the reactor and its’ robotic decommissioning as also in the transportation and storage of radioactive waste. The use of nuclear fuel can lead to significant health threats from the unregulated emission of radioactive isotopes; which include Krypton, Xenon, Argon and Tritium and could cause long term physical harm to residents in surrounding and nearby areas. These releases are unregulated because the nuclear industry considers these particular radioactive elements to be biologically inconsequential. The transportation and storage of radioactive waste could also become a global security problem, if the use of nuclear energy is adopted on a wide basis. A completely new and potentially catastrophic dimension would be added to global security with the deliberate creation of new and potentially vulnerable targets for terrorist strikes. While the advanced nations would be able to shore up reasonable levels of security the same may not be true of the developing countries where weaker management systems could lead to grave risks; witness the variation in the effectiveness of different management sy stems in disaster control in the Chernobyl and Three Mile Island episodes. Nuclear proliferation remains a major issue. The USA is planning to go ahead with the selling of weapons grade nuclear fuel to India, (a non signatory to the Nuclear Proliferation Treaty and a country with a history of surreptitious manufacture of nuclear weapons) for use in power generation. If it is India today, can Pakistan be far behind? The prospect of an atomic bomb capable Pakistan getting access to Yellow Cake, an intermediary for the production of enriched uranium, is a frightful thought; enough to send shivers down the spine of the developed world. The energy crisis enveloping the globe has a number of dimensions, all equally worrying. The availability of fossil fuels is reducing sharply because of resource depletion, price spikes and geopolitical reasons. Greenhouse emissions of carbon dioxide are leading to global warming with far reaching ecological effects that could one day threaten the existence of the world. The development of renewable energy sources, wind and solar, once touted as the best solutions, have been largely unsuccessful and remained in the realm of experimentation; useful only in small isolated pockets. In this situation, while nuclear energy does appear to have most of the answers, the concerns of the environmentalists and the anti nuclear campaigners also remain very valid. 2. Impact on Contemporary Business Organisations The UK has always been in the forefront of development of nuclear technology. The work carried out by British scientists in the 1940s was renewed after the war and it is pertinent to recall that the world’s first nuclear power reactor started in the UK in 1956. Twenty three nuclear reactors power the country’s nuclear plants, leading to the generation of a total of 75 billion kWh of electricity, a fifth of the country’s requirement. However, all but three of these plants are scheduled to close by 2020, with consequent effects on the economy and operations of contemporary business organisations. The major dilemma for business and economy is to find alternative sources for energy, nuclear or otherwise to fill this expected gap in energy production and to provide for increased needs. 2020 is not so far away. The other major factor staring British economy in the face is the prospect of importing 90 % of its gas requirement by 2025. The country and its economy is looking at a huge energy deficit, an issue that will need resolution in the very near future. The Confederation of British Industry (CBI) has, in a widely publicised call in April this year, asked the Government to clarify its’ stand on longer term carbon emission policy to enable low carbon emission sources like nuclear fuel to play an important role. The CBI has also stated very categorically that nuclear power is the only proven low-carbon technology able to deliver consistent supplies of electricity on a large scale. The advantages of stable operating costs, the availability of nuclear fuel from politically stable countries and the ability to store uranium are practical reasons to work towards the development and commissioning of more nuclear plants. In addition, the operating costs of nuclear power are stable because the cost of fuel varies between only 5 and 10% of total operating costs. The cost of building nuclear power plants, as of now, is far more than that of conventional oil, gas and coal fired plants. Operating costs are however not just lower but also expected to be stable and independent of recurring political upheavals. Two factors are however set to change these circumstances. The cost of fossil fuel, especially oil is on a sharp upward path, threatening to throw all cost projections out of gear. The expected depletion in gas resource and consequent compulsion to buy increasing quantities from outside is also going to come with its own consequences, increased costs definitely one of them. While manufacturers of nuclear power plants are working on reduction of capital cost, a â€Å"significant increase in the price of natural gas could make new nuclear plants economically competitive even without further reductions in their capital costs.†(Taylor, 2004) The CBI in its statement of April also stated that companies would seriously consider investing in new, capital intensive nuclear plants, subject to the introduction of a correct non-discriminatory policy on carbon emission; beyond the present policy which is unclear after 2012. Intense concern about the current situation also made it say that â€Å"an energy policy based on crossing fingers and the use of the prayer mat is not acceptable†.(Nuclear Power in the United Kingdom, 2006) Contemporary businesses, not just in the UK but across the globe are wrestling with an energy crisis, the widespread usage of fast depleting fossil fuels, rocketing oil prices currently resting in the low 70s (USD per barrel), and the continuous spectre of carbon dioxide emissions and global warming. The real advantage of nuclear energy is its potency. One pound of uranium contains the energy equivalent of roughly one million pounds of coal. Such potency means that nuclear powers energy potential is vast, clearly sustainable as a long-term resource. It also means nuclear’s environmental impact is inherently low. With so much energy coming from such a small volume of material, producing nuclear fuel requires much less exploration, mining, transportation, and collection, with all their attendant environmental problems, than do fossil fuels. For example, a 1,000-megawatt nuclear plant requires one refueling per year, whereas a similarly sized coal plant requires 80 rail cars of coal per day. (Lorenzini, 2005) The gridlock appears to be slowly tightening with nuclear power possibly the only solution to the intensifying problem. 3. Likely Future Scenario The future scenario in use of fuel for energy and its development is probably going to move in reasonably predictable directions. All across the globe, awareness on global warming and its possibly devastating repercussions has heightened considerably. Every natural calamity, be it the Tsunami in Indonesia, earthquakes in Pakistan, the arrival of the Katrina in the United States or the melting of the glaciers in the Himalayas finds an immediate media connection to carbon dioxide emissions, the greenhouse effect and global warming. This phenomenon, coupled with the instability of supply and the rising cost of fossil fuels is going to lead to an expansion of nuclear power both in the USA and the UK. Governmental restrictions on use of nuclear power are slowly being dismantled as governments across the globe see the advantages of going nuclear for power generation. Along with increase in nuclear power generation, governments across continents will try to develop renewable energy sources for power generation. Renewable energy has not really made much headway despite concerted efforts in the last thirty years. Nearly 90 % of the global energy production is obtained from fossil sources and most of the rest comes from nuclear power. Wind and hydro energy can be harnessed only in suitable locations that have access to huge amounts of rainfall, fast flowing rivers or conditions suitable for setting up wind farms. Countries with access to fossil fuels, oil, gas and coal will of course continue to depend heavily upon these sources for power. However, the threat of emissions and consequent ozone layer depletion will nudge all countries towards the development of alternative sources. The rising costs of oil, essential for vehicular and air transportation will lead to its curtailment for use as as fuel for all but essential reasons. Renewable sources will of course fill a part of the yawning power gap which appears to be looming on the horizon but nuclear power is also very much a part of the final answer. It is the one energy source that today combines the benefits of displacing the use of fossil fuels, minimising pressure on land, avoiding resource depletion and restricting harmful emissions. The UK and the USA, both countries with over regulated nuclear power generation environments will necessarily open up their laws to ease the setting up of newer power facilities, based on nuclear fuels. The building of nuclear energy capacity necessarily comes with the enormous added responsibility of ensuring public health and safety, involving first, the storage and containment of harmful waste material and second, the prevention of dangerous nuclear material going into the hands of rogue states and terrorist organisations. Contemporary business organisations will need to survive in similar circumstances for the next few years until additional nuclear and renewable energy facilities are set up. This is essentially going to be a slow, expensive and careful process and the period of infrastructure build up will be open to all the risks that exist today, namely uncertain supplies and skyrocketing prices. It is only with the spread and extensive use of nuclear power on a global basis, the establishment and strict enforcement of protocols for responsible and peaceful use of nuclear energy and the rooting out of rogue states and terrorist organisations that businesses will be able to witness and take advantage of stability in supplies and cost of energy, free of the worry of a global environmental threat from emissions of harmful gases. 4. Summary and Way Forward In the UK the 2006 review of the energy policy has put development of nuclear energy firmly on agenda and public opinion is also now veering towards its use. It has been determined that all the new plants will have to be built by the private sector with internalised waste and decommissioning costs. All barriers that threaten to slow down investment will be looked at very carefully, without compromising public safety; new and speedier licensing procedures will also be considered. The use of nuclear fuel for energy is gaining ground globally after years of stagnation but some of the old concerns still remain. Environmentalists and anti nuclear campaigners have a number of worries, most of which concern safety, the prevention of hazards from nuclear plants and the misuse of nuclear fuel by rogue states, international criminals and terrorist organisations. While their strident objections to the theory of nuclear energy being much cleaner and â€Å"greener†than energy derived from fossil fuels could be taken to be substantially incorrect, it would be presumptuous to brand all their worries about safety and the possibility of nuclear proliferation as facile and alarmist. Many of these concerns are still valid and do need attention. The two major areas that demand consideration are the disposal of nuclear waste and the reprocessing of spent fuel. The sustainability of nuclear power, the ability to make it work for long time frames and to think of it as a real long term solution to the global power issue depends upon obtaining an acceptable and workable solution to the problem of managing nuclear waste. Nuclear wastes are classified differently from other toxic residues and need to be kept safely for thousands of years, whereas the timeframe for non radioactive toxics of between 50 to 70 years is far less. Work is needed in this area on two fronts, the carrying out of continuous scientific research, needing significant governmental and institutional funding to find a solution to the storage problem, and a fresh look at regulatory laws to assess whether they can be revisited without compromising safety. Reprocessing relates to the process in which plutonium and uranium are chemically separated from spent fuel for reuse, as is done in France. Reprocessing allows for more complete usage and tapping of the energy potential of nuclear fuel and makes waste management easier, reducing both bulk and long term hazards which could arise from the waste. However, the separated plutonium could create a potential nuclear threat, if it finds its way to the wrong hands, and again will need very careful security. After years of stagnation, the several demands of the twenty first century have combined to make the world seriously think of the need for nuclear power. The increase in demand for power and electricity in the developing world, the sharply eroding global resources of fossil fuels, the continuing global geopolitical instability, the skyrocketing prices of oil and gas, and the need to severely restrict carbon emissions are forcing nations to turn towards nuclear fuel for release from their energy worries. The need of the moment is to think and to cooperate in this global mission. As Paul Lorenzini states: The most critical step is to build a consensus among energy planners and policymakers that sustainability as a policy goal should include nuclear power. Bringing nuclear power back into the mix for energy planning means shedding ideological biases. It means openness of thinking to resolve the tension between the human desire for modernization and the global need for sustainability (2005) References Caldicott, H, 2005, Nuclear Power is the problem, not a solution, Common Dreams News Center, www.commondreams.org/views05/0415-23.htm Clapp, R. W., 2006 Nuclear Power and Public Health. Environmental Health Perspectives, 113(11), 720+.Questia database: http://www.questia.com/PM.qst?a=od=5012166072 [27 Aug 2006] Lorenzini, P., 2005, Spring. A Second Look at Nuclear Power: By Overlooking Nuclear Power in the Quest for Clean Energy, We Are Condemning Ourselves to a Future of Increased Fossil Fuel Use. Issues in Science and Technology, 21, 31+. Questia database: http://www.questia.com/PM.qst?a=od=5009414160 [27 Aug 2006] Nuclear Power in the United Kingdom, 2006, World Nuclear Association, www.world-nuclear.org/info/inf84.htm [27 Aug 2006] Taylor, J. J. (2004, Spring). The Nuclear Power Bargain: The Potential Benefits Are Enormous If We Can Continue to Make Progress on Safety, Environmental, Fuel Supply, and Proliferation Concerns. Issues in Science and Technology, 20, 41+. Questia database: http://www.questia.com/PM.qst?a=od=5006170378 [27 Aug 2006] Webster, P, 2006, Britain goes nuclear to beat energy crisis, Times Online, www.timesonline.co.uk/article/0,,2-2184192,00.html [27 Aug 2006]
Sunday, August 4, 2019
OCCUPATIONAL BACK INJURIES DURING MANUAL HANDLING OF MATERIAL Essay
INDEX PAGE INTRODUCTION     3 ERGONOMICS     4 OBJECTIVES OF ERGONOMICS     4 RESULTS OF ERGONOMIC APPLICATIONS     5 THE BACK STRUTURE     6 BACK AND BACK PROBLEMS     6 Back injuries     6 Causes of back injuries     7 The following are common causes of back injuries:–     7 Back injury prevention     8 Back injury-preventative techniques     8 Techniques     9 Strategies     9 ORIGINAL LIFTING MODEL     10 Strain index (SI) =     10 Action limit     11 Maximum permissible limit     11 Administrative controls     12 Engineering controls     12 Limitations of the NIOSH lifting model     13 LEGISLATIVE TRENDS: STANDARDS, GUIDELINES AND INTERVENTION PROGRAMMES     13 CONCLUSION     14 APENDIX 1     15 REFERENCES     16 OCCUPATIONAL BACK INJURIES DURING MANUAL HANDLING OF MATERIAL INTRODUCTION Almost one third of all disabling injuries at work, temporary or permanent are related to manual handling of objects. Many of these incidents are avoidable and are the consequence of inadequate or simplistic bio-mechanical task analysis. Injuries associated with manual materials handling have grown substantially and are currently estimated to exceed several billion dollars annually in the USA. In addition to the compensation costs are the tremendous costs associated with the suffering of the impaired workers. Manual material handling injuries can result from lifting, lowering, pushing, pulling or carrying objects while performing activities . Some of the most traumatic and costly manual material handling injuries impact on the back, more specifically the lower back has been the area of concern in most studies examining the low back pain associated with manual material handling. Lifting, handling and dragging loads involve a good deal of static effort, enough to classify as h... ... are not included.5 LEGISLATIVE TRENDS: STANDARDS, GUIDELINES AND INTERVENTION PROGRAMMES Ever since the 19th century, government bodies in the developed nations have attempted, for social as well as economic reasons, to influence the way industry runs itself. Industries now have to comply with regulations, which limit worker exposure to the health - threatening aspects of their job. The requirement for good working conditions is not a new one. The Occupational Health and Safety Act of 1970 requires all employees to â€Å"provide their employees with a workplace free from recognised serious hazards†irrespective of whether these hazards are covered by specific standards. If poor ergonomics constitutes a hazard, then employers are required to act. Ergonomic Safety and Health Management Rules specify what constitutes an â€Å"ergonomic hazard†and what actions to take to remove the hazard. The rules assist employers in complying with already existing legislation.4 CONCLUSION Through compliance with legislative trends, understanding of the back structure, and Health and Safety training programmes, the universal prevalence of occupational back injuries can be reduced and even prevented.
Saturday, August 3, 2019
Wedding Speech Delivered by the Groom -- Wedding Toasts Roasts Speeche
Wedding Speech Delivered by the Groom Before I start I have to ask... Do you like my outfit?... you see, I asked the tailor for Versace... but he thought I said "Liberace"! Ladies, Gentlemen, Friends, Relatives and any stray pedestrians who may have wandered in. On behalf of my wife and I... or as I prefer to call her "my most recent ex-girlfriend", welcome to our wedding. I hope you're all enjoying yourselves on this special day. Its great to see you all and I can honestly say it would have been rubbish without you. It would also have been a lot cheaper without you, but that's beside the point. We'd like to thank my new Father-in-law for his kind words and good wishes. And to thank both my new in-laws for all the help (both organisational and financial) they have given us in arranging this reception. I'd like to thank them personally also for all the kindness and generosity they have shown me over the last 8 years, especially after we got off on the wrong foot 8 years ago with the awful blocked toilet incident. I won't go into the details here, but suffice to say their toilet was not blocked before I went in there, but it was very blocked when I left... and overflowing. Nothing much was said at the time, but I did notice on my next visit that the bathroom carpet had been replaced with easy wipe laminate floor! So for that discretion and everything else: thank you. We'd also like to thank my mum for ... ...or those who don't know, Nuala is the one with the plaster cast on her arm, sustained in an arm-wrestling contest to decide who would be the chief bridesmaid. And Shiv who is the chief bridesmaid! We'd like to thank both of you for all the support given to the bride today as well as the other kind of support offered on the way home from the hen do. But most of all we want to thank you for blending in so well with the table cloths. So if you would all stand and raise your glasses and join me in toasting the bridesmaids... "The bridesmaids!" OK I could go on all night, trotting out the usual tired old jokes and fictitious anecdotes, but instead I'm going to leave that to the best man. Thank you.
Friday, August 2, 2019
Influence of TV And Radio :: essays papers
Influence of TV And Radio One of the most important means of communication by pictures and sounds is the television. Most of what we learn comes from television. Just think of all that we see in just one hour of television-commercials, educational programs, sitcoms, etc. The TV is another source that we can learn from about lands far away, people, and places. You can sit in your living room while visiting Europe, Asia, or even Australia. Television is a huge influence on our daily lives, as shown by how much time is spent staring at its screen. Unfortunately, the heaviest viewers of television are children. Of course, there are worthwhile programs on TV suitable for kids, such as Sesame Street and the Magic School Bus, but just imagine what a child would think if he saw just one episode of Melrose Place. Do we tell the children that this is acceptable? Radio is important, but is not used as frequently anymore due to the birth of television. We hear the news and can listen to different opinions of controversial subjects. Millions of families used to gather around the radio to listen to dramas, light comedies, variety shows, live music, and other programs. However, people can communicate a lot more quickly between any two points either on land, at sea, in the sky, or also in space, with the use of the radio. Politically, the radio made it possible for the people to be informed about government policies directly. Radio was "born" in the twenties, and "died" in the forties. Because the depression made listening the only amusement people could afford, the thirties were radio's finest years. Later, in the fifties television was making a breakthrough. By 1961, 88% of the United States' households had two sets which were in use for an average of 5 hours a day. Television killed off small-club boxing, minor league baseball, and practically any other activity that meant leaving the living room. Television is the perfect baby-sitter. We just plop our kids down in front of the set, while we go among our business. Television has spent more time raising our kids than we have. Children no longer play baseball or swing on the swings in the park or play tag in the back yard as much anymore. Television and radio have, obviously, been a huge influence on our lives. But the main question is: have they been a good influence or a bad
Confrontation
Cindy Xin Wang MBA 5500 Managing Confrontation Writing Assignment 1 Mar. 25th, 2010 Confrontation: Based on My Personal Experience Confrontation is never a pleasant process for both the one who conducts the action and the one who is confronted with. According to the textbook, crucial confrontation is defined as face-to-face accountability discussions with the aim to address and close the gap between expectations and actual performances. The gap is usually violated expectations, broken promises, or poor performances. Confrontation is not a simple discussion but deals with an urgent high-steak issue. The differences between what was promised or expected and what actually happened are very common in real life. Most of the time, however, people try to avoid confronting others even though they want to hold someone accountable. They believe the action is either unnecessary or unaffordable. After the first lectures in this class, I began to realize that some confrontations do not necessarily to be unpleasant. Some confrontations could be very effective and helpful in improving results and relationships if conducting well. Before confronting people, first, we need to analyze the consequences of either confronting or not confronting this person. Then we need to identify the real issue by unbundling with CPR (context, patter, and relation), and distill to a single sentence for the whole situation. Then we can make a decision on whether to confront this person or not. Also, to master confrontations, we need to avoid silence, violence, and hogs. This paper will discover a potential confrontation that has troubled me for quite a long time, and use the skills that I learned in this class to examine the situation and decide whether to conduct confrontation or not. The issue that bothers me for a long time is a grading discrepancy with a professor. I took that class year. I got 89. 6% of that class. Most of the students in that class were the same major with me and we’ve know each other very well. The score that I disagree with is the participation points. The grading policy was the quality of the I thought I was misjudged as Confrontation Cindy Xin Wang MBA 5500 Managing Confrontation Writing Assignment 1 Mar. 25th, 2010 Confrontation: Based on My Personal Experience Confrontation is never a pleasant process for both the one who conducts the action and the one who is confronted with. According to the textbook, crucial confrontation is defined as face-to-face accountability discussions with the aim to address and close the gap between expectations and actual performances. The gap is usually violated expectations, broken promises, or poor performances. Confrontation is not a simple discussion but deals with an urgent high-steak issue. The differences between what was promised or expected and what actually happened are very common in real life. Most of the time, however, people try to avoid confronting others even though they want to hold someone accountable. They believe the action is either unnecessary or unaffordable. After the first lectures in this class, I began to realize that some confrontations do not necessarily to be unpleasant. Some confrontations could be very effective and helpful in improving results and relationships if conducting well. Before confronting people, first, we need to analyze the consequences of either confronting or not confronting this person. Then we need to identify the real issue by unbundling with CPR (context, patter, and relation), and distill to a single sentence for the whole situation. Then we can make a decision on whether to confront this person or not. Also, to master confrontations, we need to avoid silence, violence, and hogs. This paper will discover a potential confrontation that has troubled me for quite a long time, and use the skills that I learned in this class to examine the situation and decide whether to conduct confrontation or not. The issue that bothers me for a long time is a grading discrepancy with a professor. I took that class year. I got 89. 6% of that class. Most of the students in that class were the same major with me and we’ve know each other very well. The score that I disagree with is the participation points. The grading policy was the quality of the I thought I was misjudged as
Thursday, August 1, 2019
Sodium Thiosulfate Reaction
eLearning 2009 Publication No. 91860 Rate of Reaction of Sodium Thiosulfate and Hydrochloric Acid Rate Laws Introduction The purpose of this demonstration is to investigate the effect of sodium thiosulfate concentration on the rate of reaction of sodium thiosulfate with hydrochloric acid. The reaction, which produces solid sulfur, will be followed by measuring the time needed for the reaction mixture to become opaque. The results will be analyzed graphically to determine the order of reaction the mathematical relationship between the reactant concentration and the rate.Concepts †¢ Kinetics †¢ Order of reaction †¢ Rate law †¢ 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 Precaution s 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 1–5 and clean the bottom of each beaker. 2. Draw a large â€Å"X†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 â€Å"X. †3. Using separate graduated cylinders for the solution and water, measure and add the required amounts of 0. 15 M sodium th iosulfate 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 1–5. 91860 011509 Flinn Scientificâ€â€Teaching 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 â€Å"X†is no longer visible. Record the rea ction time in seconds in the data table. . Repeat steps 7 and 8 with beakers 2–5. 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 toFlinn Suggested Disposal Method #26b. Tips †¢ 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 â€Å"X†is easily seen and measured. †¢ The reac tion 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. †¢ 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. †¢ 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. †¢ When lower concentrations o f 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. †¢ 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 HS2O3– ions, The HS2O3– ion is a reactive intermediate, reacting further with additional S2O32– ions to produce polymeric ions containing multiple S atoms. When the chain of S atoms in a polymeric ion becomes long enough, it â€Å"closes†in on itself to form a ring of elemental sulfur (S8). â€⠀œ  S2O32– + H+ <  > HS2O3 â€â€Ã¢â‚¬â€ – Hâ€â€Sâ€â€SO3– + nS2O32– > Hâ€â€Sâ€â€(S)nâ€â€SO3 + nSO32– –  – – Hâ€â€Sâ€â€Snâ€â€SO3 <  > H+ + Sâ€â€Snâ€â€SO3 â€â€Ã¢â‚¬â€ – Sâ€â€S7â€â€SO3 > S8 + SO32– –2–  © 2009 Flinn Scientific, Inc. All Rights Reserved. 91860 Discussion Sodium thiosulfate reacts with hydrochloric acid to form sulfur 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-axisâ€â€the reaction slows down as the reactant concentration decreases. The rate of a reaction is inversely proportional to reaction time.A plot of concentratio n 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, sec–1) . 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 –3–  © 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 Kâ €“12 Evidence, models, and explanation Constancy, change, and measurement Content Standards: Grades 9–12 Content Standard A: Science as Inquiry Content Standard B: Physical Science, structure and properties of matter, chemical reactions, motions and forcesFlinn Scientificâ€â€Teaching 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 Scientificâ€â€Teaching 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 Lawsâ€â€Student 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 Lawsâ€â€Student La boratory 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. –4–  © 2009 Flinn Scientific, Inc. All Rights Reserved. 91860
Subscribe to:
Posts (Atom)