Laws of Thermochemistry and Enthalpy Equations

Thermochemical equations are just like other balanced equations except they also specify the heat flow for the reaction. The heat flow is listed to the right of the equation using the symbol ΔH. The most common units are kilojoules, kJ. Here are two thermochemical equations: H2 (g)  ½ O2 (g) → H2O (l); ΔH -285.8 kJ HgO (s) → Hg (l)  ½ O2 (g); ΔH 90.7 kJ Writing Thermochemical Equations When you write thermochemical equations, be sure to keep the following points in mind: Coefficients refer to the number of moles. Thus, for the first equation, -282.8 kJ is the ΔH when 1 mol of H2O (l) is formed from 1 mol H2 (g) and  ½ mol O2.Enthalpy changes for a phase change, so the enthalpy of a substance depends on whether is it is a solid, liquid, or gas. Be sure to specify the phase of the reactants and products using (s), (l), or (g) and be sure to look up the correct ΔH from the  heat of formation tables. The symbol (aq) is used for species in a water (aqueous) solution.​The enthalpy of a substance depends upon temperature. Ideally, you should specify the temperature at which a reaction is carried out. When you look at a table of heats of formation, notice that the temperature of the ΔH is given. For homework problems, and unless otherwise specified, the  temperature is assumed to be 25 °C. In the real world, ​the  temperature may be different and thermochemical calculations can be more difficult. Properties of Thermochemical Equations Certain laws or rules apply when using thermochemical equations: ΔH is directly proportional to the quantity of a substance that reacts or is produced by a reaction. Enthalpy is directly proportional to mass. Therefore, if you double the coefficients in an equation, then the value of ΔH is multiplied by two. For example:H2 (g)  ½ O2 (g) → H2O (l); ΔH -285.8 kJ2 H2 (g) O2 (g) → 2 H2O (l); ΔH -571.6 kJΔH for a reaction is equal in magnitude but opposite in sign to ΔH for the reverse reaction. For example:HgO (s) → Hg (l)  ½ O2 (g); ΔH 90.7 kJHg (l)  ½ O2 (l) → HgO (s); ΔH -90.7 kJThis law is commonly applied to phase changes, although it is true when you reverse any thermochemical reaction.ΔH is independent of the number of steps involved. This rule is called Hesss Law. It states that ΔH for a reaction is the same whether it occurs in one step or in a series of steps. Another way to look at it is to remember that ΔH is a state property, so it must be independent of the path of a reaction.If Reaction (1) Reaction (2) Reaction (3), then ΔH3 ΔH1 ΔH2

Symbolism in The Lottery, by Shirley Jackson Essay example

When most people play the lottery today, they think about having wealth. Generally, people who win are happy about it whether they win one dollar or a million. The lottery in our society has grown to support education and it is often worth several million dollars. Usually, the winner of the lottery gains a lot of recognition for the money they win. But what would happen if there was a small town where people held a yearly lottery in which the â€Å"winner† was the member of the town who was not sacrificed? This question is answered in Shirley Jackson’s short story, â€Å"The Lottery.† In reading this story, and reading literary criticism about the story, there were many symbols and much symbolism in this story. 1 Biographical Analysis Shirley†¦show more content†¦Americans were moving back to a time where they wanted life to be simple and orderly. There was also a need to go back to traditional values and a need for conformity (Miss Cellania). While people enjoyed seeing the Cleveland Indians win the World Series, The Philadelphia Eagles win the NFL and while they were being entertained by beautiful women like Lauren Bacall, Ava Gardner and Rita Hayworth (PCM Entertainment and Trivia Network) Jackson was entertaining a different audience through her short story. It was interesting that many people were upset with Jackson about this story. One reason was because her publisher spread a rumor that Jackson was a practicing witch (Miss Cellania). Although Jackson dabbled in mysticism and read tarot cards, the idea that she was a witch was a joke. â€Å"The Lottery† was frightening during that time and it still is today. Jackson wanted to show what happened when people blindly followed a tradition just b ecause it was a tradition. â€Å"The Lottery revealed an uncomfortable truth about the human psyche and, in doing so, became a classic piece of American Literature† (Miss Celinnia). 3 Symbols and Symbolism in â€Å"The Lottery† There were many symbols in this short story. Many researchers state that several symbols refer to Christianity. As an example, the last name of one of the women, Mrs. Delacroix, was a French name meaning â€Å"of theShow MoreRelatedSymbolism In The Lottery, By Shirley Jackson869 Words   |  4 PagesSymbolism is used throughout The Lottery in the character names. Author, Shirley Jackson, uses the name of, Mr. Graves, to foreshadow the story and explain what â€Å"The Lottery† really is. Mr. Graves is the one who carries the three-legged stool which could indicate two things: the Trinity, the Father, Son, and Holy Spirit, or it could mean the past, present and future, saying that â€Å"The Lottery† will always be among the people of the village. In addition, he is also the owner of the post office andRead MoreSymbolism Of The Lottery By Shirley Jackson926 Words   |  4 PagesWhen incorporated well, symbolism enhanc es a story’s overall impact. Shirley Jackson’s short story â€Å"The Lottery† contains symbolism to affect the readers’ feelings as well as add interest. The story begins with the villagers gathering at the square to participate in the lottery. The villagers chat while waiting for the event to begin. After Mr. Summers comes with a black box, he stirs the pieces of paper in the box. The narrators describe the lottery as an old ritual that the community continuesRead MoreSymbolism Of The Lottery By Shirley Jackson1577 Words   |  7 PagesShirley Jackson s The Lottery , is a story that is filled with symbolism. The author uses symbolism to help her represent human nature as tainted, no matter how pure one thinks of himself or herself, or how pure their environment may seem to be. The story is very effective in raising many questions about the pointless nature of humanity regarding tradition and violence. The Lottery clearly expresses Jackson s feelings concerning mankind?s evil nature hiding behind traditions and ritualsRead MoreSymbolism In The Lottery By Shirley Jackson879 Words   |  4 PagesShirley Jackson, the author of the short story â€Å"The Lottery† is an unusual story of a town caught in a trap of following tradition. Shirley Jackson uses many symbols in the story to relate to the theme. By doing this it helps the reader understand the story and the message she is trying to get across. Jackson uses tone, setting, and symbolism to conduct a theme for her readers. By doing this she creates connections to the theme by using the black box and old man Warner as a symbol. Old man WarnerRead MoreUse of Symbolism in The Lottery by Shirley Jackson1146 Words   |  5 Pageswhat is known as Symbolism. Symbolism is the use of object, name, or person to represent an idea. If a name is being use, a name such as autumn can represent the adulthood of a human. Creatures such as an Eagle, represents ‘Freedom’ and ‘America’. Even inanimate objects can represent ideas; the light bulb represents ideas that just sparked into a character’s head. In the short story, â€Å"The Lottery† by Shirley Jackson, a village has just entered the month of June, meaning that the lottery is to begin.Read MoreSymbolism in The Lottery, by Shirley Jackson Essay748 Words   |  3 PagesThe Lottery: Symbolism In her story â€Å"The Lottery†, Shirley Jackson manages to catch the readers’ attention and ultimately shock them with an unexpected ending; all of which help her emphasize her critique toward the dark side of human nature and the evil that resides, sometimes, in those who we less expect it from. Jackson uses symbolism throughout the story that helps her set the mood and also makes the readers wonder and analyze the senseless violence and cruelty in their own lives. It all startsRead MoreUse of Symbolism in The Lottery by Shirley Jackson954 Words   |  4 PagesSymbolism means like any place, person or thing that is something but can be interpreted in a different way. The Lottery by Shirley Jackson is a short story that shows symbolism, to give hints about the story in all the characters and objects in the story. This Short story takes place in the summer where a small town has a lottery every year round. The person that wins the lottery has a huge impact on the town and the crops that grow in it. Old man Warner is the oldest in the town andRead More, Symbolism, And Themes In The Lottery, By Shirley Jackson1252 Words   |  6 PagesShirley Jackson’s The Lottery, is a realism story that was written for the main purpose of entertainment. Jackson writes about a small village that gathers every year for an event they call â€Å"The Lottery†. Every head of households comes up and draws a slip of paper from the box. Bill Hutchinson draws the first slip of paper with the black dot but Tessie Hutchinson quickly exclaims the lottery is not fair. Mr. Summers then puts five slips of paper back into the box, one for each of the family membersRead MoreTheme Of Symbolism In The Lottery By Shirley Jackson960 Words   |  4 Pagesagainst it shall be purged with death. The beauty of this world is just a mere mask to hide its monstrosity.Tear off its mask and you shall be bestowed upon the gift of the cruelty of this world. Shirley Jackson’s short story the â€Å"Lottery† illustrates the characte r Tessie Hutchinson as a figure of symbolism as it leads to the theme that the norms of society isolates those who are a victim of labels and expectations because they decorate the origins of sins therefore premonition of the ruin to someRead More The Use of Symbolism in The Lottery by Shirley Jackson Essay938 Words   |  4 PagesThe Use of Symbolism in The Lottery by Shirley Jackson Within the first few lines of Shirley Jacksons The Lottery we are faced with such adjectives as clear, sunny, fresh and warmth. She goes on to paint a picture of small children just out of school for the summer, as the townspeople gather for the annual Lottery. This leads us to believe that the rest of the story is as cheery as the summer day initially described. We as the readers are virtually unaware of the horrible senseless events

Benefits Of Recycling Essay Example For Students

Benefits Of Recycling Essay Lately the earths capacity to tolerate exploitation and absorb solid wastes disposal has diminished, due to excess trashing. People dispose lots of stuff, and simply do not care. Therefore scientists found out a way to reuse things and that process was called recycling. This new approach seemed quite successful at the beginning, until its true identity appeared. Recycling first started as mans best friend, people were intrigued by this new phenomena. What could be better than using things that were already used. Recycling has been very useful especially that man is constantly consuming, burning up, wearing out, replacing and disposing at an alarming rate.(Durning 1992). However, unfortunately recycling has proven that it is quite costly. Although recycling of wastes material solves the problem of garbage disposal at landfills, and saves resources, it does nevertheless entail large hidden costs in collecting, sorting and manufacturing; therefore, it is necessary for the go!vernment to overcome such problems of recycling to be worth while and for manufacturers and consumers to consume less. Recycling has proven its efficiency in solving the problem of garbage disposal at landfills1. By the accumulation of garbage throughout the years, space available for garbage has largely diminished. In the states for example almost 67% of their waste stream ends up in landfills.(Scott 25). This has in fact increased the price of disposal. As Kimball stated tipping fees at landfills, is so often prohibitive(3), and some cannot find landfills to dump their garbage. It can cost up to $158 to pick a ton of garbage and dispose it.(Consumer Reports 1994). Beside, these landfills pollute their surroundings area with lots of hazardous materials and contaminate underground water. To discover the contamination of the underground water it would be 12 yeas after the poisons-benzene; formaldehyde; mercury; and BCEE- have actually contaminated the land, and had sunk 24 feet into the ground contaminating about 50 million gallons of underground water.(Dahir 94). Besides these lands could b!e used in more useful ways such as building schools, hospitals, or simply turning them into large green areas to purify the air. This problem is practically acute in Egypt, since we do find even in central areas of the city, piles of garbage disposal very near to residential areas. Recycling would therefore eliminate this problem and protect the environment. If we consider burning as an alternative, well it is not very advantageous, so often burning is done in incinerators. According to Plenum, incineration is the process of disposing of the Combustible portion of the community wastes(81). This burning pollutes the air in the area around it. It is not the way to solve the problem of recycling because it solving one problem by creating another which is air pollution. In this process a number of pollutants are emitted which poisons the air. Carbon dioxide and lead are by products of burning that most health organisations consider highly toxicating. These by products affect children mentally and physically. In addition, carbon dioxide is considered one of the main reasons of global warming because the molecule itself captures heat an stores it in it thus creating the green house effect. Besides plastics are rather toxicating when burnt according to Plenum, Acrylic type plastics emit HCN gas, Bromine components that are added to pl!astics re sults in the emission of HBr , which are all dangerous pollutants (157). Obviously burning cannot be considered an alternative and as stated in Consumer Reports, Recycling does help to keep garbage out of landfills and incinerators, both of which pose environmental problems.(Feb 1994). Although burning lessens the physical amount of the waste materials, it is considered one of the easiest way to pollute the air. Though these are great advantages to us and the environment, but recycling costs more than you could imagine. A study found that when the cost of garbage is calculated by volume, landfilling and recycling costs are roughly the same. Recycling does not appear to save any money, this applies to most of the European countries and the United States and studies have lately proven so. Recycling is a good thing, but it costs money.(Boerner and Chilton 7). This view has been confirmed by John E. Jacobson, who is the president of AUS, a consulting firm in Philadelphia who stated that it is often more expensive to recycle than to manufacture from raw material. The process goes through lots of phases. First collecting and sorting garbage and second is manufacturing and marketing. Collection is a phase by itself. In developed countries such as the States, Europe, and the Far East, the people have a great deal of awareness of the situation. People know that recycling is important and wo!uld save us lots and lots of things. So the country itself provided facilities to help the people recycle such as machines that recycle cans on the spot and gives 2.5 cents/can and recycables-collecting programs and others. These collecting programs are costly, besides they do not work in apartment buildings. Beside, vehicles that transport these materials are not so cheap, besides most of these trucks capacities are wasted by bulky objects. Especially when trash contains a lot of plastic containers. More tractors more rounds are required to collect recycables. This adds to the cost. We took plastics out of recycling programs because we could not afford to drive around with trucks with 45% of their collection capacity taken up by air.(Consumer Reports 1994).As for the sorting process it entails lots of man power and tools, both of which are very expensive. The material cannot simply be all fed into one big machine and then boom we have recycled material. No, every kind of material must be pu t alone then fed into big recycling machines. This process of separation or sorting costs money. Manufacturers have to hire labourers to sort out glass from aluminium from cardboard from tin and so on. According to Consumer Reports, the sorting equipment and the man power involved in the process is a big investment (1994). It is important to know that this process of collecting and sorting is particularly expensive in developed countries where sophisticated tools are used where man power is rather limited and expensive. However, in developing countries like Egypt, the process of collecting and sorting are rather primitive and is carried out by the Zabaleen or a second-hand car. This makes it less expensive than developed countries. A Lesson Before Dying EssayThis rapid leap in our lives have led us to create recycling and hopefully it will lead us to look for a way to better plan it. Better planing for recycling will help prevent the problems faced now by recycling. If it could be made that it satisfies the needed conditions previously mentioned, to be cost-efficient, not time consuming, and a better quality of products, this would be like a dream come true. Recycling should be cost-efficient because what all nations are facing are massive economical problems. Financing these programs is one hell of a job and if it has to be done anyway, then we should at least look for ways to make it cost efficient. People should learn to use and reuse, rather than use and dispose. If we can use things more than once and could save energy then why not do so. Reuse means getting more use out of a product to reduce the waste stream. Many so-called disposable items, such as plastic cups, knives, and forks, can actually be wash ed and used several!times. (Scott 25). As we can see the benefits are over-estimated, and the costs are under-estimated. What we should do is not only look for an alternative but also look for other ways to improve recycling. The natural resources will not last for ever, eventually everything comes to an end and the end is very near to our natural resources. What is of greater importance is to find alternatives to such resources if they actually become extinct. Recycling is backed by most of the general public, for its ideas of saving the environment, energy, and virgin material. But it is not that good or that efficient it still costs money and is not that safe. Recycling does not necessarily provide for safer or more environmentally sound disposal than landfilling or incinerators. The recycling process itself generates enormous amounts of hazardous wastes.(Schaumburg 32). In addition it will decrease and maybe solve the problem of the ever increasing pollution. Imagine that every time som!eone throws a piece of paper in the garbage is similar to a person cutting a leaf off a tree. This is what happens when one does so, so recycling was the way to solve such a problemBibliography:

Regulation And Reform Of Euthanasia Essay Example For Students

Regulation And Reform Of Euthanasia Essay Regulation and Reform of Euthanasia Throughout the twentieth century, major scientific and medical advances have greatly enhanced the life expectancy of the average person. However, there are many instances where doctors can preserve life artificially. In these cases, where the patient suffers from a terminal disease or remains in a persistent vegetative state (PVS), the question becomes whether to prolong their life even though it may consist of pain and suffering. One of the landmark cases that involve euthanasia is that of Karen Ann Quinlan. Quinlan, a twenty-one year old New Jersey resident, overdosed on pills and alcohol in 1975. She was rushed to the hospital where her physical condition gradually deteriorated to a vegetative state. The doctors determined she had no chance of recovery. Karens parents requested she be removed from the respirator. The hospital denied their request. The Quinlans then directed their request to the court. The superior court denied their request. They took their request to the new Jersey Supreme court where the decision was reversed. Karen was removed from the respirator. To everyones surprise, Karen began breathing on her own and was transferred to a nursing home, where she remained in a coma, fed through tubes, until she died in July 1985, ten years later (Humphry and Wickett, 108).The Quinlan case brought to the forefront patients desire to die a proud, quiet death and the complications caused by the advancement of medical technology to prolong life. Individuals should have the right to die with dignity in the event of a terminal illness if he or she wants to. Those who oppose legalizing euthanasia and assisted suicide say that this could lead to voluntary killing of the aged and infirm. I agree that there may be danger of abuse of euthanasia; therefore, I support passing legislation that monitors and regulates physician assisted suicide. In order to clarify my position, I will first distinguish between passive and active euthanasia and their implications. In addition, I will examine the legal issues behind the Quinlan case and other similar cases. Finally, I will propose the argument that with proper legislation, physician assisted suicide is often a more favorable alternative to allowing patients to suffer needlessly. O. Ruth Russell defines active or positive euthanasia as a positive merciful act taken deliberately to end futile suffering or a meaningless existence where death is induced either by direct action to terminate life or by indirect action such as in giving drugs in amounts that will clearly hasten death (19). Active euthanasia is illegal in most states. Passive or negative euthanasia means discontinuing or desisting from the use of extraordinary life-sustaining measures or heroic efforts to prolong life in hopeless cases when such prolongation seems an unwarranted extension of either suffering or unconsciousness (Russell, 20). There are several different views associated with active and passive euthanasia. While some doctors and patients may accept passive euthanasia, many reject active euthanasia. Robert G. Twycross strongly disagrees with the practice of euthanasia, especially active euthanasia in Where There Is Hope, There Is Life: A View From the Hospice. Twycross uses cancer patients as an example and asserts that often patients opt for euthanasia because initially they do not feel the relieves of medication being and their pain is used as a channel of mental anguish (162). Therefore, unable to stand the intolerable pain, patients feel that euthanasia is the best way out. However, Twycross argues that compared with patients and physically fit people, doctors have been noted to express a greater fear of death, more rejection of personnel death and significantly more negative death imagery (159). Twycross argument adds a whole new dimension to the euthanasia argument. If in fact doctors are reluctant to accept euthanasia in their practice, they may discourage their patients from opting for it. .u7029a2f7932811968ffc2491acfc0b9d , .u7029a2f7932811968ffc2491acfc0b9d .postImageUrl , .u7029a2f7932811968ffc2491acfc0b9d .centered-text-area { min-height: 80px; position: relative; } .u7029a2f7932811968ffc2491acfc0b9d , .u7029a2f7932811968ffc2491acfc0b9d:hover , .u7029a2f7932811968ffc2491acfc0b9d:visited , .u7029a2f7932811968ffc2491acfc0b9d:active { border:0!important; } .u7029a2f7932811968ffc2491acfc0b9d .clearfix:after { content: ""; display: table; clear: both; } .u7029a2f7932811968ffc2491acfc0b9d { display: block; transition: background-color 250ms; webkit-transition: background-color 250ms; width: 100%; opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #95A5A6; } .u7029a2f7932811968ffc2491acfc0b9d:active , .u7029a2f7932811968ffc2491acfc0b9d:hover { opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #2C3E50; } .u7029a2f7932811968ffc2491acfc0b9d .centered-text-area { width: 100%; position: relative ; } .u7029a2f7932811968ffc2491acfc0b9d .ctaText { border-bottom: 0 solid #fff; color: #2980B9; font-size: 16px; font-weight: bold; margin: 0; padding: 0; text-decoration: underline; } .u7029a2f7932811968ffc2491acfc0b9d .postTitle { color: #FFFFFF; font-size: 16px; font-weight: 600; margin: 0; padding: 0; width: 100%; } .u7029a2f7932811968ffc2491acfc0b9d .ctaButton { background-color: #7F8C8D!important; color: #2980B9; border: none; border-radius: 3px; box-shadow: none; font-size: 14px; font-weight: bold; line-height: 26px; moz-border-radius: 3px; text-align: center; text-decoration: none; text-shadow: none; width: 80px; min-height: 80px; background: url(https://artscolumbia.org/wp-content/plugins/intelly-related-posts/assets/images/simple-arrow.png)no-repeat; position: absolute; right: 0; top: 0; } .u7029a2f7932811968ffc2491acfc0b9d:hover .ctaButton { background-color: #34495E!important; } .u7029a2f7932811968ffc2491acfc0b9d .centered-text { display: table; height: 80px; padding-left : 18px; top: 0; } .u7029a2f7932811968ffc2491acfc0b9d .u7029a2f7932811968ffc2491acfc0b9d-content { display: table-cell; margin: 0; padding: 0; padding-right: 108px; position: relative; vertical-align: middle; width: 100%; } .u7029a2f7932811968ffc2491acfc0b9d:after { content: ""; display: block; clear: both; } READ: Americas Growing Pains Essay Several complications arise at this point. Even if euthanasia is legalized, will doctors accept the new treatment and will patients be able to go to any doctor before worrying about whether or not the doctor will accept euthanasia when the time comes? The doctor-patient relationship and the ethical connotations of euthanasia are really important to my argument too. Dr. Malcolm C. Todd, president-elect of the American Medical Association, told the press that mercy killings have their place in certain uncorrectable fatal illnesses, but that decisions in such cases should not be left to the attending physician alone, (Russell, 46). English Essays