The Cumulative Cost Of Additional Wakefulness Dose...

For Article Critique one I chose the article â€Å"The Cumulative Cost of Additional Wakefulness: Dose-Response Effects on Neurobehavioral Functions and Sleep Physiology From Chronic Sleep Restriction and Total Sleep Deprivation (P.A., H., Greg, M., Janet M., M., David F., D. (2003)†. This article was written and submitted for publication in 2003. I found this article very interesting due to the fact that I myself, work off a very unusual work schedule and feel that I am a victim of sleep deprivation personally. For example, I find that I maintain from 4-7.5 hours of sleep a night. This has become very taxing on me not only mentally but psychically. This is why I chose this article, it is personally relatable. This study was conducted using randomization of experimental groups. The participants were randomly chosen for each group, the 4 hour, 6 hour and 8 hour group (P.A., H., Greg, M., Janet M., M., David F., D. (2003). This was not a blind study, both the participants and the researchers knew which group they would be in and what they were being monitored for at all times. Participants also had full consent at all times, meaning they knew what was going to happen and when it was going to happen at all times. Of this specific study I do not think that these parameters, experimental and fully consensual, had any effect on the study itself or the given results. I believe that these results, which I am about to share with you, are valid and that this study can be replicated

To Kill a Mockingbird Essay Free Essays

Many people don’t realize it, but our world matures with age, and the people along with it. Society’s attitudes towards things, its moral education, and its general opinion on the world have all changed to adapt to the problems of today. In Harper’s Lee, To Kill A Mockingbird, Lee shows how the world was before our moral development, and the evilness that the world once lived in. We will write a custom essay sample on To Kill a Mockingbird Essay or any similar topic only for you Order Now To Kill A Mockingbird shows the causes and effects of injustice through oppression of the innocent, racism, and existence of social inequality. Throughout the novel, a symbol of â€Å"mockingbird† appears. The title â€Å"To Kill a Mockingbird† has a true meaning to it, and that is: the oppression of the innocent. Miss Maudie explains in the novel that, â€Å"’Mockingbirds don’t do one thing, but sing their hearts out for us. That’s why it’s a sin to kill a mockingbird. ‘† In the novel, the mockingbirds are innocent people who are harmed by injustice, and in unnecessary ways. Several times in the novel, the oppression of the innocent is displayed. Jem for one, is a mockingbird. He is innocent, but assaulted by Bob Ewell, purely on vengeance, only because Atticus defended Tom Robinson, and he wanted to get pay back. Boo Radley is also a mockingbird. He is emotionally damaged by his cruel father as a child, but everyone leads to believe that he is a creepy maniac. Scout mentions near the end of the book, â€Å"’Well it’d be sort of like shootin’ a mockingbird, wouldn’t it? ‘† (page 370) This refers to Boo Radley and how Scout feels if they were to hurt Boo Radley anymore; he has suffered enough from their injustice community. Another mockingbird is Tom Robinson. He was charged guilty of raping May Ewell, even though he was likely to be not guilty. There was not enough evidence against him, but he was still convicted. After his death, Mr. Underwood compares his murder to â€Å"the senseless slaughter of songbirds†. This is once again, referring to mockingbirds, and the oppression of the innocent. In the town of Maycomb, the existence of social inequality is very, very vibrant. Everyone is Maycomb is on a social standing pyramid. Depending where you are on the pyramid determines how much respect you’ll receive from the towns folk. For example, in the novel, Aunt Alexandra forbids Scout to invite Walter Cunningham over for dinner. The following quote from Aunt Alexandra describes why: â€Å"’Jean Lousie, there is no doubt in my mind that they’re good folks. But they’re not our kind of folks. ‘† (page 299) This represents that Aunt Alexandra and the Finches are higher up on the social standings, therefore making the Cunningham’s lower, and not in he same social class. The Finches are on pretty much the top of the social standings, with the towns people below them. The farmers, like the Cunningham’s are lower than the towns people. Below them are the Ewells, disrespectful and inferior. And even farther below them are the Negroes or coloured folk. During the day of the trial, people sat in the square to eat lunch. Only the people in the same social class would sit together. This quote from Scout represents just that: â€Å"In a far corner of the square, the Negroes sat quietly in the sun. † (page 214) This shows that the Negroes sat together because they are in the same social class, which is indeed the lowest in Maycomb. With that in mind, people like Bob Ewell, can take advantage of that. He picks on those who are below him because he wants to make himself feel more powerful, like bullies do. This shows the effects of inequality of social classes in Maycomb. Racism is also a factor of social inequality, and is a huge element in To Kill A Mockingbird. It is displayed by almost every character in the book with racial slurs, and derogatory terms, many of which refer to Tom Robinson. For example, this quote from Cecil Jacobs verbally harasses Tom Robinson: â€Å"’My folks said your daddy was a disgrace an’ that nigger oughta hang from the water tank. ‘† (page 102) Although it may seem like only the white people are being racist to the coloured folk, it’s also the other way around as well. Jem and Scout experience this first hand. When they go to the First Purchase Church with Calpurnia, the people there did not accept them because of their different skin colour. So just like the expression, â€Å"what’s go around comes around. † Although, this does not happen often between the two skin colours because there is a huge segregation between them. They live in completely different areas of Maycomb because the coloured folk are isolated from the white people, unless you work for a white person. That brings us to how coloured folk are not aloud to be employed to anything they want. They’re basically slaves to the white people, and do not have the choice to do what they heart desires. Although we have matured from this stage, there is still quite a bit of racism in today’s world. To Kill A Mocking has taught many of the past generation and even the new generation many lessons about injustice. This novel shows the causes and effects of injustice through oppression of the innocent, racism, and existence of social inequality. Harper Lee’s, To Kill A Mockingbird, made many people realize how unjust the world was and still is in some countries. With one step at a time, there will soon be a day without any injustice or crime in the world thanks to moral messages like this novel. How to cite To Kill a Mockingbird Essay, Essays To Kill a Mockingbird Essay Free Essays Over the course of three years, a seemingly quiet town faced the unexpected. A fruitless trial was held, innocence was lost, blood was shed, and an unlikely friend emerged. Written by Harper Lee, To Kill a Mockingbird takes place in the city of Macomb during the sass. We will write a custom essay sample on To Kill a Mockingbird Essay or any similar topic only for you Order Now The book tells the story through the childish views of Jean Louse Finch (Scout), as she and her brother Gem face Instances of human evil. Alongside the two is their father Tactics, who gradually teaches the two to fight against their own well-being and do what they feel is right. In the story, Lee demonstrates Scout’s personality growth through her newfound morals, ability to look past misconceptions morals, and rejection of gender stereotypes. Scout gradually acquires moral values by learning how to reduce her urge to resort to unnecessary violence. Concerned, Tactics lectures Scout about her tendency of fighting with classmates: â€Å"†¦ You Just hold your head high and keep those fists down. No matter what anybody says to you, don’t let ‘me get your goat† (Lee 76). Tactics disapproves of Scout’s quick decisions of resorting to violence and asks her to earn to control her temper. Due to Scout being young, Tactics is worried about the consequences that come with getting into fights frequently and because he worries that Scout will follow a wrong path. After the talk, Scout does in fact obey his advice about controlling her temper and walks away from a fight: â€Å"l drew bead on him, remembered what Tactics had said, then dropped my fists and walked away, ‘Scout’s a coward! ‘ ringing in my ears. It was the first time I had ever walked away from a fight. Somehow, if I fought Cecil I would let Tactics down. Tactics so rarely asked Gem and me to do something for him, I could take being called a coward for him† (Lee 76). Scout, for the first time In her inure life, walked away from a fight all because of what Tactics had said earlier. She showed that she is growing up by being able to keep herself under control of her emotions. Finch’s thought of personal honor is shifted from flitting being a solution to being able to not cause an uproar for no reason. Though It seems to be the right decision at the time, unnecessary violence only makes matters worse. As the story progresses, Scout realizes that the stereotypical image of a lady isn’t what being a woman is about. Thinking over gender stereotypes, Scout talks to herself about not being handle the huge shift: â€Å"l felt the starched walls of a pink cotton penitentiary closing in on me, and for the second time in my life I thought of running away† (Lee 136). Scout takes Aunt Alexandra actions against her pants as being against her freedom. For Scout, being a lady-in-training means giving up all the things she Likes to do and replacing them with what others expect her to do, and he’ll have none of it. When Aunt Alexandra returns to her tea party with a serious look after hearing about Tom’s death, Scout sets her as a new example: â€Å"After all, if Aunt could be a lady at a time like this, so could l† (Lee 237). Looking at Aunt Alexandra, Scout took pride In following her lead. Though she still Isn’t comfortable with the guidelines that ladies must follow, Scout does pick up on the examples of the strong women in her life. Scout doesn’t ever abandon her tomboyish ways, but 1 OFF also acquires the ability to look past misconceptions. Speaking to herself, Scout thinks about how terrifying Arthur Raddled (Boo) must be: â€Å"Every night-sound I heard from my cot on the back porch was magnified three-fold; every scratch of feet on gravel was Boo Raddled seeking revenge, every passing Negro laughing in the night was Boo Raddled loose and after us; insects splashing against the screen were Boo Reader’s insane fingers picking the wire to pieces; the chicanery trees were malignant, hovering, alive† (Lee 55). Though Scout has never seen Boo before, she is quick to hint that he must be a frightening, violent person. Scout unknowingly connects something that she doesn’t know as ominous, and in Scout’s mind the whole world becomes dangerous-?every sound signaling a threat. After she met Boo, Scout looks back on how she previously treated Boo and regrets her actions: â€Å"Neighbors bring food with death and flowers with sickness and little things in between. Boo was our neighbor. He gave us two soap dolls, a broken watch and chain, a pair of good-luck pennies, and our lives. But neighbors give in return. We never put back into the tree what we took out of it: we had given him nothing, and it made me sad† (Lee 278). Once Scout realizes all of the things that Boo has done for her, she regrets not giving anything in return. As Scout begins to grow up, she is able to look at things in a new light. A part of maturing is learning to not Judge people at first glance, because the brightest of people could be found in the dark. Through To Kill a Mockingbird, Jean Louise Finch learned to avoid trouble, Just by following Attic’s orders on not causing n uproar with her fists. Through To Kill a Mockingbird, Jean Louise Finch learned that being a lady isn’t all about tea parties and frolicking in dresses, but it’s also about standing up for your own opinions. Above all, Jean Louise Finch learned that the unknown may not end up being such a scary thing after all. Maturity has a variety of definitions, but Scout learned hers as many others have-?through experience. She has matured immensely compared to how she was in the beginning of the story, but she is still only a mockingbird that has Just begun to sing. How to cite To Kill a Mockingbird Essay, Essays To Kill a Mockingbird Essay Free Essays Reading How To Kill A Mockingbird Anywhere you go in life you should always follow the moral of having to see things from others perspectives. This is a topic in a scene from Harper Lee’s To Kill a Mockingbird. Scout, the main character, talks to her father Atticus about her teacher, Miss Caroline, telling her about how Scout needs to stop reading at home. We will write a custom essay sample on To Kill a Mockingbird Essay or any similar topic only for you Order Now Harper Lee uses this scene to have Scout learn an important lesson which has to look at other people’s points of views in order to understand them. In To Kill a Mockingbird, Harper Lee uses setting to show one of the major themes of the novel which is one cannot understand another until he looks at things from a different perspective. For example, Atticus tells Scout she will â€Å"get along better with all kinds of folk if she can consider things from his point of view- climb into his skin and walk around in it,† after Scout comes home from school which is where Miss Caroline had spoken to her about not having her read with Atticus. This creates the author’s effect because it helps Scout think about Miss Caroline’s point of view. The author may use this to develop the theme of racism because it shows that you should think about what other people may be thinking. This scene has an importance in characterization because it leads to having Scout learn coming of age. For example, â€Å"She had learned not to hand something to a Cunningham, for one thing, but if Walter and I had put ourselves in her shoes we’d have seen it was an honest mistake on her part. † We realize Scout is learning about Miss Caroline and why she would want her to stop reading at home. This creates the author’s effect because it shows Scout is growing up and she is thinking of other people’s point of view. The author may use this to develop the theme of coming of age because it shows that Scout had realized that she should think about the other person’s perspective. In To Kill a Mockingbird, Harper Lee uses conflict to have Scout realize to understand a person’s choices. For example, â€Å"Bit by bit, I told him the day’s misfortunes,† Scout had said. â€Å"If you can learn a simple trick, Scout, you’ll get along a lot better with all kinds of folks. You never really understand a person until you consider things from his point of view. † Atticus had informed Scout. This creates the author’s effect because it shows Scout conflict resulted in her learning about other people’s point of views. The author may use this to develop the theme of coming of age because it shows Scout realizing about Miss Caroline’s point of view. Harper Lee used setting, characterization and conflict to develop one of the major themes of the novel: in order to understand a person, you must look through their eyes. This important theme is shown throughout the whole novel. How to cite To Kill a Mockingbird Essay, Essay examples To Kill a Mockingbird Essay Free Essays To Kill a Mockingbird In Harper Lee’s To Kill a Mockingbird Calpurnia has become the motherly figure in Scout’s life by teaching her lessons, morals and values. Calpurnia taught Scout to write when she was bored on a rainy day â€Å"Calpurnia was to blame for this†¦then copying out a chapter of the bible beneath† (p24). This shows Calpurnia is not just cooking and cleaning; she entertains her and has a special connection with her. We will write a custom essay sample on To Kill a Mockingbird Essay or any similar topic only for you Order Now Another thing Calpurnia is doing for Scout is teaching her manners and mannerisms â€Å"†¦that boy’s yo’ comp’ny and if he wants to eat up the table cloth you let him, you hear† (p32). Here Calpurnia shows Scout that she needs to be polite when they have company in their home. Calpurnia is more to Scout than a nanny: she is more like a mother to her. â€Å"Perhaps Calpurnia sensed that my day had been a grim one†¦ she knew I loved crackling bread† (p38). Cal has a motherly instinct with the Finch children and she knows when something is wrong in their lives just like a mother. Throughout the novel Harper Lee’s To Kill a Mockingbird it shows that Calpurnia is a major part of both Jem and Scouts life. She has taught them both so much from how to write to how they should be acting as they mature and if things were any different Jem and Scout probably would have turned out different due to the massive influence that Calpurnia has had on them. How to cite To Kill a Mockingbird Essay, Essay examples To Kill a Mockingbird Essay Free Essays Even though he is quite huh amble about his integrity and claims taking Tom’s case was just like taking any other case, it ha d to of taken courage to do such a thing. Tactics broke away from the mainstream by sticks Eng to his gut and did what was right. Following Tactics’ footsteps is Scout, Scout learns very quickly from her faith err the idea of courage and integrity. We will write a custom essay sample on To Kill a Mockingbird Essay or any similar topic only for you Order Now SCOUt learns these things at a very young age, although h she might not realize that her open mindedness takes a vast amount of courage. To truly u understand and give people a chance while being so young is inspiring. When Scout stands up for Walter Cunningham in class she knows she could get in trouble but does it anyway. This is the exact idea of Tactics’ definition of courage. Another character with plenty of brave examples is Tom Robinson, Tactics’ clip .NET. When Tom spoke in court about pitying the white girl (Male) he knew that it would nag err the others but he spoke his true feelings anyway. At the end of it all Tom gets sent to prison, he tries to escape hill knowing full well that he had a very small chance in succeeding but once e again he does it anyway. Tom knew he was â€Å"licked† but saw it through till the end. The Finch’s neighbor, mysterious Boo Raddled, does several unexpected acts of kindness that took a pretty good amount of courage. Boo doesn’t like going outside and bee Eng around a lot of people, but he makes some decisions that risk being outside and being by MO re people than usual. For example, Boo sees Scout, Jam, and Dill snooping around his proper TTY so he puts some resents in the hole off big tree for the children to have. Boo also saves Soc UT from a scalding fire by giving her a thick blanket, Boo could’ve badly hurt himself but he risks t hat to save an innocent child’s life. Not everyone would risk their own life for another’s, but Boo does just that which shows his amazing amount of courage and integrity. So, what is your definition of courage? Make it your goal to fulfill that define Zion multiple times just like Tactics, Scout, Tom, and Boo have. Harper Lee’s â€Å"To Kill a Mock inning† sis book about courage, and to aspire to be a good person. How to cite To Kill a Mockingbird Essay, Essays

Neutral tones by Thomas Hardy and Sonnet XVIII by William Shakespeare Essay Example For Students

Neutral tones by Thomas Hardy and Sonnet XVIII by William Shakespeare Essay William Shakespeares poem Shall I compare thee to a summers day? or Sonnet XVIII as it is commonly referred to was composed at the end of the sixteenth century in the renaissance period. It is an Elizabethan love sonnet. In this era, the people had a taste for witty poems with a common stance for the lover to woo his mistress. Thomas Hardys poem Neutral Tones was in contrast written on a later date during the Victorian era. Although the poems were written in very different time periods, they both share a similar relevance to their conception of love. Both poems are focused on love as their subject matter throughout, although this does not mean that they are alike in structure, form or style. In fact the opposite is true as the two poems contrast in their portrayal of love. Shakespeares poem Sonnet XVIII is in fact a sonnet comprising of fourteen iambic pentameter decasyllabic lines which are divided into three quatrains and one rhyming couplet. Hardys poem, in contrast, is written in four by four line stanzas. However both poems have a regular rhyming scheme, Shakespeares quatrains have alternate coupling rhymes contrasted to ABBA rhyming scheme, which has a definite end to each stanza, just like the end to the relationship. Sonnet XVIII uses positive language and is principally based around summer imagery, which gives a sense of a flourishing, prosperous relationship, in contrast with Neutral Tones which uses negative tones and winter imagery for Hardy to discuss his love affair with his mistress that appears to be a more than static relationship. The vowels used by both authors are somewhat significant to their portrayal of how their relationships unfolded. Shakespeare uses majorily sharp vowels -e, i, as an indication to his perfect love whereas Hardy uses softer, more dragging vowels -a, o, u, along with soft feminine rhymes, which provides a mood of melancholy and wistfulness and tells the reader that the love has gone from his mistress and he. A very interesting point in comparing these two poems is that Shakespeares poem is written in the present tense and is a poetic argument unfolding in front of us, whereas Hardys poem is in the past tense and is merely explaining what happened in the break up of the relationship. Shakespeares Sonnet XVIII opens with a witty, light-hearted tone- Shall I compare thee to a summers day? This first line is a rhetorical question, and shows the mistress as a woman full of charisma and allure. The rhetorical question gives a facetious and playful beginning to the sonnet and gives the impression of a thriving, loving, passionate relationship. The way, in which the opening line uses summer imagery, -Summers day- suggests the loving, amorous, ardent relationship, which Shakespeare intended to present to the readers. The speaker continues to express this love he feels for his mistress in the next line- Thou art more lovely and more temperate; gives the reader a sense of Shakespeare illustrating his mistress as a woman full of physical beauty, which is an analogy of how he feels intimately for her. All the language used here is positive, it is suggestive of how the mistress is more beautiful than a blossoming summers day. Following the theme of beauty and affectionateness, Shakespeare uses the phrase, Darling buds of May to tell her how much he cares about her, and this gives an indication of Shakespeares belief that their love has the potential to blossom, grow and develop: And summers lease hath all too short a date This line tells the reader how Shakespeare thinks that perhaps his mistress life is too short to fulfil the real potential of their love. This shows how Shakespeare loves her and expresses sadness at the thought that their love must one day come to an end. The quote -summers lease- is used to refer to his mistress being as gorgeous as summer and that her lease, a binding contract with an agreed date, is too short for him and their love. Throughout the following four lines the imagery of summer is shown to be fading away and turning dull all the time. Personification of the sun and the sky is used to signify this experience- Sometime too hot the eye of heaven shines, And often is his gold complexion dimmd The imagery eye of heaven is used to represent the sun. These two lines show how the sun is so beautiful with its gold complexion but although it is extremely attractive (too hot) it will die down and hide away from sight inevitably: And every fair from fair some-time declines The repetition of fair shows the happiness of both the season of summer and the woman talked about in the poem. This quote says that all good things however must come to an end some time. Shakespeare shows how he believes that their love could possibly end one day by chance despite how much they care for each other and feel for each other now- Metaphorical importance in the poem EssayHardy shows his readers how he failed to fully understand the relationship he was involved in through the next line- Over tedious riddles of years ago; This line is suggestive of the two people standing and talking about how their relationship went wrong. riddles of years ago implies that the relationship was a complicated one which ended a long time ago. The use of the word tedious implies that the relationship had become dull and burdensome upon the speaker. The line: And some words played between us to and fro is a symbolic line through it showing how the relationship was one argument. to and fro implies that the two could not talk as though in love but instead were constantly fighting in contrast to Shakespeares poem which gives a loving relationship. Again this is another hint as to why the relationship was destined to corruption. The final line in the second stanza is one of a paradoxical nature: -On which lost the more by our love it shows how the relationship was not to be a successful one from the outset. In the third stanza, enjambment is used to indicate the continuation of the speakers feelings after the relationship is over. The use of- The smile on your mouth was the deadest thing is suggestive of how the speaker could see through the mistress false face and see the forced, unreal smile. This forced smile is a sign that the mistress was not interested in the speaker, and that the zest had gone from the relationship so an end was the only option. Alive enough to have strength to die Again Hardy uses paradoxical language here as he does with the following line- And a grin of bitterness swept thereby A relationship is supposed to be a happy, joyful thing. The use of grin of bitterness here shows the narrators real feelings and exemplifies how the narrator is aware of the untrue smile. The stanza finishes with leader dots at the end of: Like an ominous bird a-wing This phrase suggests that something of a bad nature is about to happen. The grin of bitterness is an omen to the narrator that the relationship is over. Personification is used: bird a-wing The forth stanza revives the first stanza and the landscape illustrated earlier in the poem. It is the relationship viewed in retrospect. The last stanza opens with Since then The use of a semicolon here shows the narrator looking back over the relationship and thinking about what has happened: Since then keen lessons hat love deceives edged with grayish leaves. The whole verse is a continuous rhyme with the last word of each line. This gives the verse a list-like quality showing the anger in the narrator. The use of alliteration in the second line of this stanza: And wrings with wrong -also gives it a list-like quality. This style creates a sense of bitterness in the speaker, which is contradictory to the narrators feelings at the start. The language used here is also symbolic of the bitterness felt by the narrator. Keen lessons that love deceives is an ambiguous phrase. The narrator is talking about other relationships he has learned from or possibly the lesson he has learnt from this woman. The tone of this stanza reflects his discontent and shows how, with the passing of time, his resentment has intensified. The final two lines of the poem present a very paradoxical idea of the relationship, as they imply that the more they talk, the less fond of each other they grow. The third line suggests that the narrator has become somewhat hateful towards the mistress. He refers to the mistress using God-curst sun which is a use of negative imagery. The poem finishes on a very definite note. Hardy uses pathetic fallacy to show how everything is dead. The poem ends where it began, at the side of a pond, and as a sign of the end, the pond is edged with grayish leaves implying that their relationship is dead. Although both writers use very similar methods to show their experiences of love, the two methods contrast in relation to style and imagery. Both poems share the same topic and are very closely related in terms of form and meaning but a clear comparison can be made to distinguish the two different attitudes towards love and relationships. My preference is Hardys poem, as I prefer the four by four line stanzas. I find this breaks up the poem better. The language describing this failed attempt at love compared to Shakespeares poem of a thriving love, is to the point and creates a sense of pity towards the speaker.

Purpose The Purpose Of This Lab Is To Yield Isoamyl Acetate, A Banana

Purpose: The purpose of this lab is to yield isoamyl acetate, a banana fragrance, by reacting acetic acid and isoamyl alcohol. By reacting a carboxylic acid with an alcohol we synthesize an ester, in this case isoamyl acetate. Procedure: 1) Obtain 8.5 mL of isoamyl alcohol and 15.0 mL of acetic acid in a 100-mL round-bottomed flask. 2) Add dropwise 5 mL of concentrated sulfuric acid with boiling chips and reflux for one hour. 3) At the end of the reflux cool the round-bottomed flask in a cold water bath. 4) Pour the contents of the flask into a beaker with 40mL of ice water. 5) Pour the beaker contents into a separatory funnel and mix with occasional venting. If the two layers do not separate add 2-3 g of solid sodium chloride to increase the density of the aqueous layer which will separate the two layers. 6) Separate the organic layer and wash with 15 mL sodium bicarbonate. Keep washing with sodium bicarbonate until it is neutral or slightly basic. This might take 1 to 2 more washings. 7) After the last washing, wash again with 15 mL of distilled water. 8) Transfer the organic layer to a dry flask and add 1-2 g of anhydrous magnesium sulfate. Stopper the flask and occasionally stir. 9) Gravity filter the solution into a 100 mL round-bottomed flask and perform a simple distillation. Collect the portion that distills between 130oC and 145oC into a pre-weighed vial. 10) Record the refractive index, mass, and percent yield. Data: Percent Yield: Hypothetical 8.5 mL isoamyl alcohol x .81g/mL = 6.9 g isoamyl alcohol 6.9 g x 1 mol isoamyl alcohol/88 g = .0781 mol isoamyl alcohol 1 mol isoamyl alcohol : 1 mol isoamyl acetate .0781 mol isoamyl acetate x 130 g/ 1mol = 10.1530 g isoamyl acetate Actual 12.4344 g 6.6333 g 5.8011 g Percent Yield = Actual / Hypothetical = 5.8011 g/ 10.1530 g = 57.14 % Refractive Index: Measured refractive index: 1.400 at 20oC Merck Index refractive index: 1.405 at 20oC Discussion: The reaction that took place, carboxylic acid with an alcohol forming an ester, can be done two different ways: The one used in this lab was method A. The R group in this case is a methyl group and the R' is the (CH3) 2CH(CH2)2 group. The acid used is sulfuric acid. This method does not present as high yields as method B. The reason for this is that the reaction is reversible. To help increase yield in this method an excess of one of the primary reactants is used. In this case the acetic acid. The isoamyl alcohol is a limiting reactant and is used to calculate the percent yield. The first step in the reaction mechanism is that the carboxylic acid is protonated. The double bonded O is reacted with the acid H+ and the double bond between the carbon and the oxygen goes to the oxygen molecule to a pair of electrons and with the acid H+ ion, an OH+ forms. In the same step the O from the OH group on the alcohol attaches to the C atom of the carboxylic acid giving the carbon atom 4 bonds after it lost one by giving the other oxygen an electron pair. The H+, from the newly added alcohol, is then separated with the oxygen taking the electron pair. Then the H+ attaches to the side OH group forming H2O. This H2O is then removed, leaving one OH group, which in turn returns to its primary state by losing an H+ and forming the double bond again (giving carbon 4 bonds). Research: The product has many uses. These uses include being a component in pear oil and banana oil, and pear flavor in mineral water, syrups, and lacquers. Isoamyl Acetate is also used in photography, bronzing, and dyeing of artificial silk. It aids in the manufacturing of artificial silk. The product is one of many ingredients used in cigarettes, and it also is used as a pheromone. Its characteristics make it a very popular compound. Its smell has been argued to be that of pear, apple, or banana, yet most popularly banana. It also has gives flavor of pear. These characteristics make it popular to be used as a fragrance, and flavor additives. It can be found naturally in pears, apples, and

What Is Statistical Significance How Is It Calculated

What Is Statistical Significance How Is It Calculated SAT / ACT Prep Online Guides and Tips If you've ever read a wild headline like, "Study Shows Chewing Rocks Prevents Cancer," you've probably wondered how that could be possible. If you look closer at this type of article you may find that the sample size for the study was a mere handful of people. If one person in a group of five chewed rocks and didn't get cancer, does that mean chewing rocks prevented cancer? Definitely not. The study for such a conclusion doesn't have statistical significance- though the study was performed, its conclusions don't really mean anything because the sample size was small. So what is statistical significance, and how do you calculate it? In this article, we'll cover what it is, when it's used, and go step-by-step through the process of determining if an experiment is statistically significant on your own. What Is Statistical Significance? As I mentioned above, the fake study about chewing rocks isn't statistically significant. What that means is that the conclusion reached in it isn't valid, because there's not enough evidence that what happened was not random chance. A statistically significant result would be one where, after rigorous testing, you reach a certain degree of confidence in the results. We call that degree of confidence our confidence level, which demonstrates how sure we are that our data was not skewed by random chance. More specifically, the confidence level is the likelihood that an interval will contain values for the parameter we're testing. There are three major ways of determining statistical significance: If you run an experiment and your p-value is less than your alpha (significance) level, your test is statistically significant If your confidence interval doesn't contain your null hypothesis value, your test is statistically significant If your p-value is less than your alpha, your confidence interval will not contain your null hypothesis value, and will therefore be statistically significant This info probably doesn't make a whole lot of sense if you're not already acquainted with the terms involved in calculating statistical significance, so let's take a look at what it means in practice. Say, for example, that we want to determine the average typing speed of 12-year-olds in America. We'll confirm our results using the second method, our confidence interval, as it's the simplest to explain quickly. First, we'll need to set our p-value, which tells us the probability of our results being at least as extreme as they were in our sample data if our null hypothesis (a statement that there is no difference between tested information), such as that all 12-year-old students type at the same speed) is true. A typical p-value is 5 percent, or 0.05, which is appropriate for many situations but can be adjusted for more sensitive experiments, such as in building airplanes. For our experiment, 5 percent is fine. If our p-value is 5 percent, our confidence level is 95 percent- it's always the inverse of your p-value. Our confidence level expresses how sure we are that, if we were to repeat our experiment with another sample, we would get the same averages- it is not a representation of the likelihood that the entire population will fall within this range. Testing the typing speed of every 12-year-old in America is unfeasible, so we'll take a sample- 100 12-year-olds from a variety of places and backgrounds within the US. Once we average all that data, we determine the average typing speed of our sample is 45 words per minute, with a standard deviation of five words per minute. From there, we can extrapolate that the average typing speed of 12-year-olds in America is somewhere between $45 - 5z$ words per minute and $45 + 5z$ words per minute. That's our confidence interval- a range of numbers we can be confident contain our true value, in this case the real average of the typing speed of 12-year-old Americans. Our z-score, ‘z,' is determined by our confidence value. In our case, given our confidence value, that would look like $45 - 5(1.96)$ and $45 + 5(1.96)$, making our confidence interval 35.2 to 54.8. A wider confidence interval, say with a standard deviation of 15 words per minute, would give us more confidence that the true average of the entire population would fall in that range ($45Â ± \bo{15}(1.96)$), but would be less accurate. More importantly for our purposes, if your confidence interval doesn't include the null hypothesis, your result is statistically significant. Since our results demonstrate that not all 12-year-olds type the same speed, our results are significant. One reason you might set your confidence rating lower is if you are concerned about sampling errors. A sampling error, which is a common cause for skewed data, is what happens when your study is based on flawed data. For example, if you polled a group of people at McDonald's about their favorite foods, you'd probably get a good amount of people saying hamburgers. If you polled the people at a vegan restaurant, you'd be unlikely to get the same results, so if your conclusion from the first study is that most peoples' favorite food is hamburgers, you're relying on a sampling error. It's important to remember that statistical significance is not necessarily a guarantee that something is objectively true. Statistical significance can be strong or weak, and researchers can factor in bias or variances to figure out how valid the conclusion is. Any rigorous study will have numerous phases of testing- one person chewing rocks and not getting cancer is not a rigorous study. Essentially, statistical significance tells you that your hypothesis has basis and is worth studying further. For example, say you have a suspicion that a quarter might be weighted unevenly. If you flip it 100 times and get 75 heads and 25 tails, that might suggest that the coin is rigged. That result, which deviates from expectations by over 5 percent, is statistically significant. Because each coin flip has a 50/50 chance of being heads or tails, these results would tell you to look deeper into it, not that your coin is definitely rigged to flip heads over tails. The results are statistically significant in that there is a clear tendency to flip heads over tails, but that itself is not an indication that the coin is flawed. What Is Statistical Significance Used For? Statistical significance is important in a variety of fields- any time you need to test whether something is effective, statistical significance plays a role. This can be very simple, like determining whether the dice produced for a tabletop role-playing game are well-balanced, or it can be very complex, like determining whether a new medicine that sometimes causes an unpleasant side effect is still worth releasing. Statistical significance is also frequently used in business to determine whether one thing is more effective than another. This is called A/B testing- two variants, one A and one B, are tested to see which is more successful. In school, you're most likely to learn about statistical significance in a science or statistics context, but it can be applied in a great number of fields. Any time you need to determine whether something is demonstrably true or just up to chance, you can use statistical significance! How to Calculate Statistical Significance Calculating statistical significance is complex- most people use calculators rather than try to solve equations by hand. Z-test calculators and t-test calculators are two ways you can drastically slim down the amount of work you have to do. However, learning how to calculate statistical significance by hand is a great way to ensure you really understand how each piece works. Let's go through the process step by step! Step 1: Set a Null Hypothesis To set up calculating statistical significance, first designate your null hypothesis, or H0. Your null hypothesis should state that there is no difference between your data sets. For example, let's say we're testing the effectiveness of a fertilizer by taking half of a group of 20 plants and treating half of them with fertilizer. Our null hypothesis will be something like, "This fertilizer will have no effect on the plant's growth." Step 2: Set an Alternative Hypothesis Next, you need an alternative hypothesis, Ha. Your alternative hypothesis is generally the opposite of your null hypothesis, so in this case it would be something like, "This fertilizer will cause the plants who get treated with it to grow faster." Step 3: Determine Your Alpha Third, you'll want to set the significance level, also known as alpha, or ÃŽ ±. The alpha is the probability of rejecting a null hypothesis when that hypothesis is true. In the case of our fertilizer example, the alpha is the probability of concluding that the fertilizer does make plants treated with it grow more when the fertilizer does not actually have an effect. An alpha of 0.05, or 5 percent, is standard, but if you're running a particularly sensitive experiment, such as testing a medicine or building an airplane, 0.01 may be more appropriate. For our fertilizer experiment, a 0.05 alpha is fine. Your confidence level is $1 - ÃŽ ±(100%)$, so if your alpha is 0.05, that makes your confidence level 95%. Again, your alpha can be changed depending on the sensitivity of the experiment, but most will use 0.05. Step 4: One- or Two-Tailed Test Fourth, you'll need to decide whether a one- or two-tailed test is more appropriate. One-tailed tests examine the relationship between two things in one direction, such as if the fertilizer makes the plant grow. A two-tailed test measures in two directions, such as if the fertilizer makes the plant grow or shrink. Since in our example we don't want to know if the plant shrinks, we'd choose a one-tailed test. But if we were testing something more complex, like whether a particular ad placement made customers more likely to click on it or less likely to click on it, a two-tailed test would be more appropriate. A two-tailed test is also appropriate if you're not sure which direction the results will go, just that you think there will be an effect. For example, if you wanted to test whether or not adding salt to boiling water while making pasta made a difference to taste, but weren't sure if it would have a positive or negative effect, you'd probably want to go with a two-tailed test. Step 5: Sample Size Next, determine your sample size. To do so, you'll conduct a power analysis, which gives you the probability of seeing your hypothesis demonstrated given a particular sample size. Statistical power tells us the probability of us accepting an alternative, true hypothesis over the null hypothesis. A higher statistical power gives lowers our probability of getting a false negative response for our experiment. In the case of our fertilizer experiment, a higher statistical power means that we will be less likely to accept that there is no effect from fertilizer when there is, in fact, an effect. A power analysis consists of four major pieces: The effect size, which tells us the magnitude of a result within the population The sample size, which tells us how many observations we have within the sample The significance level, which is our alpha The statistical power, which is the probability that we accept an alternative hypothesis if it is true Many experiments are run with a typical power, or ÃŽ ², of 80 percent. Because these calculations are complex, it's not recommended to try to calculate them by hand- instead, most people will use a calculator like this one to figure out their sample size. Conducting a power analysis lets you know how big of a sample size you'll need to determine statistical significance. If you only test on a handful of samples, you may end up with a result that's inaccurate- it may give you a false positive or a false negative. Doing an accurate power analysis helps ensure that your results are legitimate. Step 6: Find Standard Deviation Sixth, you'll be calculating the standard deviation, $s$ (also sometimes written as $ÏÆ'$). This is where the formula gets particularly complex, as this tells you how spread out your data is. The formula for standard deviation of a sample is: $$s = √{{∑(x_i – Â µ)^2}/(N – 1)}$$ In this equation, $s$ is the standard deviation $∑$ tells you to sum all the data you collected $x_i$ is each individual data $Â µ$ is the mean of your data for each group $N$ is your total sample So, to work this out, let's go with our preliminary fertilizer test on ten plants, which might give us data something like this: Plant Growth (inches) 1 2 2 1 3 4 4 5 5 3 6 1 7 5 8 4 9 4 10 4 We need to average that data, so we add it all together and divide by the total sample number. $(2 + 1 + 4 + 5 + 3 + 1 + 5 + 4 + 4 + 4) / 10 = 3.3$ Next, we subtract each sample from the average $(x_i – Â µ)$, which will look like this: Plant Growth (inches) $x_i – Â µ$ 1 2 1.3 2 1 2.3 3 4 -0.7 4 5 -1.7 5 3 0.3 6 1 2.3 7 5 -1.7 8 4 -0.7 9 4 -0.7 10 4 -0.7 Now we square all of those numbers and add them together. $1.32 + 2.32 + -0.72 + -1.72 + 0.32 + 2.32 + -1.72 + -0.72 + -0.72 + -0.72 = 20.1$ Next, we'll divide that number by the total sample number, N, minus 1. $20.1/9 = 2.23$ And finally, to find the standard deviation, we'll take the square root of that number. $√2.23=1.4933184523$ But that's not the end. We also need to calculate the variance between sample groups, if we have more than one sample group. In our case, let's say that we did a second experiment where we didn't add fertilizer so we could see what the growth looked like on its own, and these were our results: Plant Growth (inches) 1 1 2 1 3 2 4 1 5 3 6 1 7 1 8 2 9 1 10 1 So let's run through the standard deviation calculation again. #1: Average Data $1 + 1 + 2+ 1 + 3 + 1 + 1 + 2 + 1 + 1 = 14$ $14/10 = 1.4$ #2: Subtract each sample from the average $(x_i – Â µ)$. $0.4 + 0.4 + (-0.4) + 0.4 + (-1.6) + 0.4 + 0.4 + (-0.4) + 0.4 + 0.4 = 0.4$ #3: Divide the last number by the total sample number, N, minus 1. $0.4/9=0.0444$ #4: Take the square root of the previous number. $√0.0444 = 0.2107130751$ Step 7: Run Standard Error Formula Okay, now we have our two standard deviations (one for the group with fertilizer, one for the group without). Next, we need to run through the standard error formula, which is: $$s_d = √((s_1/N_1) + (s_2/N_2))$$ In this equation: $s_d$ is the standard error $s_1$ is the standard deviation of group one $N_1$ is the sample size of group one $s_2$ is the standard deviation of group two $N_2$ is the sample size of group two So let's work through this. First, let's figure out $s_1/N_1$. With our numbers, that becomes $1.4933184523/10$, or 0.14933184523. Next, let's do $s_2/N_2$. With our numbers, that becomes $0.2107130751/10$, or 0.02107130751. Next, we need to add those two numbers together. $0.14933184523 + 0.02107130751 = 0.17040315274$ And finally, we'll take the square root: $√0.17040315274 = 0.41279916756$ So our standard error $s_d$, is 0.41279916756. Step 8: Find t-Score But we're still not done! Now you're probably seeing why most people use a calculator for this. Next up: t-score. Your t-score is what allows you to compare your data to other data, which tells you the probability of the two groups being significantly different. The formula for t-score is $$t = (Â µ_1 – Â µ_2)/s_d$$ where: $t$ is the t-score $Â µ_1$ is the average of group one $Â µ_2$ is the average of group two $s_d$ is the standard error So for our numbers, this equation would look like: $t = (3.3 - 1.4)/0.41279916756$ $t = 4.60272246001$ Step 9: Find Degrees of Freedom We're almost there! Next, we'll find our degrees of freedom ($df$), which tells you how many values in a calculation can vary acceptably. To calculate this, we add the number of samples in each group and subtract two. In our case, that looks like this: $$(10 + 10) - 2 = 18$$ Step 10: Use a T-Table to Find Statistical Significance And now we'll use a t-table to figure out whether our conclusions are significant. To use the t-table, we first look on the left-hand side for our $df$, which in this case is 18. Next, scan along that row of variances until you find ours, which we'll round to 4.603. Whoa! We're off the chart! Scan upward until you see the p-values at the top of the chart and you'll find that our p-value is something smaller than 0.0005, which is well below our significance level. So is our study on whether our fertilizer makes plants grow taller valid? The final stage of determining statistical significance is comparing your p-value to your alpha. In this case, our alpha is 0.05, and our p-value is well below 0.05. Since one of the methods of determining statistical significance is to demonstrate that your p-value is less than your alpha level, we've succeeded! The data seems to suggest that our fertilizer does make plants grow, and with a p-value of 0.0005 at a significance level of 0.05, it's definitely significant! Now, if we're doing a rigorous study, we should test again on a larger scale to verify that the results can be replicated and that there weren't any other variables at work to make the plants taller. Tools to Use For Statistical Significance Calculators make calculating statistical significance a lot easier. Most people will do their calculations this way instead of by hand, as doing them without tools is more likely to introduce errors in an already sensitive process. To get you started, here are some calculators you can use to make your work simpler: How to Calculate T-Score on a TI-83 Find Sample Size and Confidence Interval T-Test Calculator T-Test Formula for Excel Find P-Value with Excel What's Next? Need to brush up on AP Stats? These free AP Statistics practice tests are exactly what you need! If you're struggling with statistics on the SAT Math section, check out this guide to strategies for mean, median, and mode! This formula sheet for AP Statistics covers all the formulas you'll need to know for a great score on your AP test!

The Halayeb Triangle

The Halayeb Triangle The Halayeb Triangle (map), also sometimes called the Hala’ib Triangle is an area of disputed land located on the border between Egypt and Sudan. The land covers an area of 7,945 square miles (20,580 square kilometers) and is named for the town of Hala’ib which is located there. The presence of the Halayeb Triangle is caused by the different locations of the Egypt-Sudan border. There is a political boundary that was set in 1899 that runs along the 22nd parallel and an administrative boundary that was set by the British in 1902. The Halayeb Triangle is located in the difference between the two and since the mid-1990s Egypt has had de facto control of the area. History of the Halayeb Triangle The first border between Egypt and Sudan  was set in 1899 when the United Kingdom  had control over the area. At that time the Anglo-Egyptian Agreement for Sudan set a political boundary between the two at 22nd parallel or along the line of 22ÌŠ N latitude. Later, in 1902 the British drew a new administrative boundary between Egypt and Sudan which gave control of the Ababda territory that was south of the 22nd parallel to Egypt. The new administrative boundary gave Sudan control of land that was north of the 22nd parallel. At that time, Sudan controlled about 18,000 square miles (46,620 sq km) of land and the villages of Hala’ib and Abu Ramad. In 1956, Sudan became independent and the disagreement over the control of the Halayeb Triangle between Sudan and Egypt began. Egypt  considered the border between the two as the 1899 political boundary, while Sudan claimed that the border was the 1902 administrative boundary. This led to both Egypt and Sudan claiming sovereignty over the region. In addition, a small area south of the 22nd parallel called Bir Tawil that was formerly administered by Egypt was claimed by neither Egypt nor Sudan at this time. As a result of this border disagreement, there have been several periods of hostility in the Halayeb Triangle since the 1950s. For example in 1958, Sudan planned to hold elections in the region and Egypt sent troops into the area. Despite these hostilities, however, both countries exercised joint control of the Halayeb Triangle until 1992 when Egypt objected to Sudan allowing exploration of the region’s coastal areas by a Canadian oil company. This led to further hostilities and an unsuccessful assassination attempt on Egypt’s then-president Hosni Mubarak. As a result, Egypt strengthened control of the Halayeb Triangle and forced all Sudanese officials out. By 1998 Egypt and Sudan  agreed to begin working on a compromise as to which country would control the Halayeb Triangle. In January 2000, Sudan withdrew all forces from the Halayeb Triangle and ceded control of the region to Egypt. Since Sudan’s withdrawal from the Halayeb Triangle in 2000, there are often still conflicts between Egypt and Sudan over control of the region. In addition, the Eastern Front, a coalition of Sudanese rebels, states that it claims the Halayeb Triangle as Sudanese because the people there are more ethnically related to Sudan. In 2010 the Sudanese President Omer Hassan Al-Bashir said, â€Å"Halayeb is Sudanese and will stay Sudanese† (Sudan Tribune, 2010). In April 2013 there were rumors that Egypt’s President Mohamed Morsi and Sudan’s President Al-Bashir had met to discuss a compromise of control over the Halayeb Triangle and the possibility of giving control of the region back to Sudan (Sanchez, 2013). Egypt denied those rumors however and claimed that the meeting was simply to strengthen cooperation between the two nations. Thus, the Halayeb Triangle still remains in Egypt’s control while Sudan claims territorial rights over the region. Geography, Climate, and Ecology of the Halayeb Triangle The Halayeb Triangle is located on the southern border of Egypt and the northern border of Sudan. It covers an area of 7,945 square miles (20,580 square kilometers) and has coastlines on the Red Sea. The area is called the Halayeb Triangle because Hala’ib is a large city within the region and the area is shaped roughly like a triangle. The southern border, about 180 miles (290 km) follows the 22nd parallel. In addition to the main, disputed portion of the Halayeb Triangle there is a small area of land called Bir Tawil that is located south of the 22nd parallel at the triangle’s westernmost tip. Bir Tawil has an area of 795 square miles (2,060 sq km) and is not claimed by Egypt or Sudan. The climate of the Halayeb Triangle is similar to that of northern Sudan. It is normally very hot and receives little precipitation outside of a rainy season. Near the Red Sea, the climate is milder and there is more precipitation. The Halayeb Triangle has a varied topography. The highest peak in the region is Mount Shendib at 6,270 feet (1,911 m). In addition, the Gebel Elba mountain area is a nature reserve that is home to Elba Mountain. This peak has an elevation of 4,708 feet (1,435 m) and is unique because its summit is considered a mist oasis because of intense dew, mist and high levels of precipitation (Wikipedia.org). This mist oasis creates a unique ecosystem in the region and also makes it a biodiversity hotspot with over 458 plant species. Settlements and People of the Halayeb Triangle The two major towns within the Halayeb Triangle are Hala’ib and Abu Ramad. Both of these towns are located on the Red Sea coast and Abu Ramad is the last stop for buses bound for Cairo and other Egyptian cities. Osief is the closest Sudanese town to the Halayeb Triangle (Wikipedia.org).Because of its lack of development, most of the people living within the Halayeb Triangle are nomads and the region has little economic activity. The Halayeb Triangle is however said to be rich in manganese. This is an element that is significant in the production of iron and steel but it is also used as an additive for gasoline and is used in alkaline batteries (Abu-Fadil, 2010). Egypt has currently been working to export ferromanganese bars to produce steel (Abu-Fadil, 2010). Due to the ongoing conflict between Egypt and Sudan over control of the Halayeb Triangle it is clear that this is an important world region and it will be interesting to observe whether it will remain in Egyptian control.

Academic writing and discourse functions Essay Example | Topics and Well Written Essays - 1000 words

Academic writing and discourse functions - Essay Example A potential argument maker takes into account all possible causes and factors of objection the critiques may come up with, and replies them in the same document. This adds a lot to the writer’s strength of argument. Language used in building up an argument is significantly different from that employed in essays and research papers. Arguments are particularly, narratives of the writer. So the writer frequently makes use of â€Å"I† and â€Å"we†, use of which is discouraged in general essays and other forms of literature. Because of the freedom of using first form, argumentative essays provide the reader with a very sound understanding of the language. Needs of effective communication can be readily met in an argumentative paper (Alo, 2010, p. 55). Particularly, the second speakers of a particular language benefit a lot from the argumentative essays in that they get a chance to learn through reading the language just the way it is commonly spoken in the every day life by the first speakers. For example, argumentation frequently involves use of phrases like â€Å"I grant that†¦., still I maintain that†¦Ã¢â‚¬  and â€Å"not even†¦, what to talk of†¦Ã¢â‚¬ . Suc h phrases not only convey the reader correct usage of phrases, but also deliver a sense of the language they form part of. Such phrases are a product of the psychology, beliefs and ideology of the native speakers of a language. That is the reason why, language is often considered as one of the best means of comprehending a nation’s culture. Academic language usually sounds very formal and organized as compared to the language we use in our daily life to communicate with one another. It lacks freedom of expression. Sentiments and proverbs are usually restrained by the level of formality expected from the writing. Although there is no point denying the fact that even argumentative language in academic writing is much formal than the