Stoichiometry Calculations Essay

Stoichiometry Calculations Essay Regina Marin Chapter 12: Stoichiometry SECTION 1 – WHAT IS STOICHIOMETRY? Mole-Mass Relationships in chemical reactions The balance equations is the main basis of stoichiometry, and that is the first thing to do when you want to measure a chemical process. The information provided by the chemical equation is interpreted according to the needs. And the mole is associated with the molecular weight, the molar ratios of an equation can be associated with certain of the substances involved by the mol mass. The transformations that occur in a chemical reaction is governed by the law of conservation of mass: Atoms are neither created nor destroyed during a chemical reaction. Let`s try to interpret an equation in terms of moles, particles, and mass. Remeber 2 important facts: The coefficient indicates the amount of molecules The coefficient also indicates the amount of moles Then lets get the mass of the reactants and the products by using conversion. Moles reactant/product * grams reactant/product / 1 mole reactant/product = grams reactant Mole Ratios We know that there is a direct relationship between mole and molecule. This relationship is Avogadros number. A mole always contains Avogadros number of molecules. Thus the relationships between molecules given by the stoichiometric coefficients are also valid for moles. When a chemical reaction in the molar ratios of reactants and products are given, if you can have fractional stoichiometric coefficients, since the amounts of molecules involved are very high, and we can talk about half mole of molecules or of a third mole of molecules. Stoichiometric coefficients indicate the proportion that the moles of reactants and products involved in a chemical reaction. SECTION 2 – STOICHIOMETRIC CALCULATIONS Stoichiometric mole-to-mole Conversion In this type of reaction the starting material is expressed in moles, and the desired substance are requested in moles. In stoichiometric calculations results are reported be rounded to two decimals. Similarly, the atomic masses of elements should be used rounded to two decimals. Recalling: Rounding to two decimal places, we use as a basis the third decimal. If this is greater than or equal to 5, increase one unit to two decimal places; if less than or equal to 4 the second decimal lacifra be retained. So let`s see the steps to make a mole to mole conversion: STEP 1: Balancing the equation Reviewing the equation we make sure that is really well balanced. We can represent the balanced equation in the data and the unknown exercise. STEP 2: Identify We need to identify the substance that we are looking for and the one that we are starting of. STEP 3: Apply the mole ratio. The moles of desired substance and starting the get from the balanced equation. Stoichiometric mole-to-mas Conversion To find the mass of a product, is enough to multiply the moles of the product by it`s molecular weight in g / mol. Stoichiometric mass-to-mass conversion Molar factor method is based on the ratio of the number of moles between two substances participating in a chemical reaction. Step 1: Balance the equation Step 2: Determine the molar factor, which is equal to the number of moles searched on the number of moles known. Step 3: Find the moles of O2 from O2 500g Step 4: Find the moles of SO3 from the O2 Step 5: We find the grams of SO3 after the SO3 mol 31.25 SECTION 3 – LIMITING REACTANTS Why do Reactions Stop? When adjusted equation, the coefficients represent the number of atoms of each element in the reactants and the products. Also represent the number of molecules and moles of reactants and products. When an equation is set, the stoichiometry is used to find the moles of a product obtained from a known number of moles of a reagent. The mole ratio between reactant and product is obtained from the fitted equation. Sometimes mistakenly believes that the reactions are always used the exact amounts of reagents. However, in normal practice it is usually an excess of one or more reactants are used, to ensure that the widest possible to react the less abundant reactive. Limiting Reactants When a reaction is stopped because just one of the reactants, that reactant is called the limiting reactant. One reactant that has been completely consumed in a chemical reaction is known by the name of limiting reagent as it determines or limits the amount of product formed. â€Å"Limiting reagent is one that is in default based on the balanced chemical equation† 2H2 + O2 → 2H2O In the equation above, What is the limiting reactant if we have 10 molecules of hydrogen and 10 oxygen molecules? Need 2 molecules per molecule of H2 O2 But we only have 10 molecules of H2 and 10 molecules of O2. The required ratio is 2: 1 But we have the proportion is 1: 1 It is clear that the excess reagent is the limiting reactant O2 and H2 is How to work with molecules is the same as working with moles. If we now put 15 moles of H2 with 5 moles of O2 so as the stoichiometry of the reaction is such that 1 mol of O2 reacts with 2 moles of H2, then the number of moles of O2 needed to react with all the H2 is 7, 5, and the number of moles of H2 required to react with all the O2 is 10. That is, that after all the oxygen has been consumed, 5 moles of hydrogen left over. The O2 is the limiting reactant One way to solve the problem of what is the limiting reagent is: Calculate the amount of product to be formed for each of the quantities to the reaction reagent. The limiting reactant is one that produces the least amount of product. Excess Reactant The reactant is completely consumed is called the limiting reagent because it determines the amount of product that can be produced in the reaction. When the limiting reactant is consumed, the reaction is stopped. The reactant reacts not completely, but plenty, is called the excess reagent. If we have a certain amount two elements or compounds to produce a chemical reaction, we can know in advance what will be the limiting reagent and excess reagent which, making some calculations based on the balanced chemical equation. SECTION 4 – PERCENT YIELD How much product? When the stoichiometric calculations for finding as a substance produced in a chemical reaction is made, it is expected that the amount produced of the substance will always be less than the amount of the substance to be obtained , this happens because not everything reacts completely converted to product , ie not all that does react 100% . Because of this, in stoichiometry concept yield percentage is included , the percent yield is a chemical reaction is the ratio between the actual performance and theoretical performance, the ratio of grams that actually occur in the reaction and grams that would be obtained if all you react is transformed into product. If a problem involving a chemical reaction term refers to the theoretical yield of a reaction means that we take as if everything becomes reactive product , otherwise we would be talking about an actual performance. The equation used to solve problems that involve the performance of a chemical reaction is as follows: . % Yield = (actual yield ( g ) ) / (theoretical yield ( g ) ) Ãâ€" 100 % If a problem of chemical reaction we give grams that actually produce a substance by reacting certain amount of reactant either molar or mass , it can find the percentage yield of the reaction using this equation, because they would not be given the actual performance and theoretical performance assuming that the substance would find completely react .

Increasing Hate Crime Awareness in the US Essay

Though latest report released last October 2006 by the US Department of Justice – FBI’s Uniform Crime Reporting (UCR) Program showed a decrease in total number of reported incidents, 7,163 in 2005 vs. 7,649 in 2004 (Hate Crime Statistics 2005), there has been an inversely growing awareness on this topic among various stakeholders – legislators, law enforcement officials, and the American public – such that term â€Å"hate crime† has become a part of everyday vernacular among Americans. Three factors contributed to this growing awareness. Firstly, the organizational initiatives, normally the offended party group in order to protect their civil rights, are taking active roles, through their advocacy campaigns, support services and education programs. Prominent proponents, among others, are American Civil Liberties Union (ACLU) for all Americans, Anti-Defamation League (ADL) for the Jewish, Parents and Friends of Lesbians and Gays (PFLAG), Massachusetts Office on Disability (MOD), La Alianza Hispana for the Latin-Hispanics and National Association for the Advancement of Colored People (NAACP) for African-American group. Secondly, the Federal Government on its part, through the DA’s Office has a Civil Rights Unit composed of attorneys for education and intervention services, working in cooperation with victim-witness advocates. In addition, Governor’s Task Force on Hate Crime has its ‘Stop the Hate Website’ Campaign promoting awareness of hate crimes and providing resources for responding to and preventing such acts. Thirdly, concerned group initiatives, such as NGOs in the likes of Southern Poverty Law Center (SPLC) that combats hate, intolerance and discrimination through education programs and litigations, play an independent, third-party role in increasing hate crime awareness.

What is British Cinema?

British cinema is the most respected industry in the world and has the impact on modern cinema. This industry is characterized by its constant debate about its distinctiveness which includes cultural and economic issues and the influence of American and European cinemas. The golden age of British cinema started in 1940 from the studios of Rank and Korda. This industry had given many actors, directors and many motion pictures (Curran and Porter, 1993). This paper covers certain aspects of British cinema industry and discusses two movies of the Drama genre released in 2009 and 2010.Both the movie is based on young generation that shows full of inspiration and enthusiasm for a particular dance form. The movies have been targeted to the youth and did good business. The movies also provided a good presentation of the present day’s culture in terms of settings, food, and clothing of characters, family types, issues faced by children in home and schools and others. These teenagers pr esented in this movie represent a different class of children altogether that have so much passion for their favorite art forms.In the recent past there have been lost of development in various forms of arts from music to dancing. Number of British, American, and Australian, Italian and many other singers and musicians are rocking the world with their music and the increased fan followings for these artists have increased. Teenagers are particularly inspired by them. The glamour of these arm forms attract millions to watch and perform. Discussion British cinema had faced the times of recession and boom. There are many factors which can be used to know the growth of this film industry.The growth can also be known by the number of movies produced. This cinema industry was boomed first time in 1910 but they again seen recession in 1920 just due to the competition with the US. The protective measures, which lead to the recovery and for the high production, Cinematograph Films Act 1927 h as been launched in 1936 Curran and Porter, 1993. As British cinema was just got recovered from the first waves of recession, it was hit by other recession waves in mid of 1970. This continued till 1980’s. Due to renewal of private and public investment, British cinema again got recovered in 1990’s.There were some movies produced during recession like Chariots of Fire (1981), which was the successful movie. Like this movie they have released many other movies and they were successful too. British industries have also launched the better technologies to edit the movie and now the movies are releasing in better picture quality. The movies have got worldwide success and these movies earn much higher as they have good picture quality, sound and the storyline like historical, cultural and artistic dimensions. These movies are also well known due to the educational behavior as these movies have some moral into it (Murphy, 2009).Many movies were produced in 2000’s but there were some movies which were highly appreciated by the viewers. Two of the movies are Fish Tank (2009) and Nowhere Boy (2009), which are from the same genre (drama) but the movies are based on the lives of teenage. Movie 1: Fish Tank (2009) Fish Tank is the movie which is based on the life of a teenage girl who got influenced by the street dancers and describes their dancing as being horrible. In this movie, Mia who is just 15 years old girl and living with her mother and sister on Essex Council Estate.She never go out of her estate as she was secured in her house because as she move out, the authorities starts troubling her and that’s why she had left her schooling. She just drinks cider most of the times, in her house. She only came out of her house when she does the street dancing otherwise she remain in her lonely flat and practice inside the house only. Once when she was roaming around in her estate, she saw a horse which was trying to get free but the horse was una ble to get free. She found it painful and brought the hammer to help the horse but she faced the anger of its three owners.Two of the owners have grabbed her to stop her but she get away from them after struggling with them. She got free just because of the dog of Mr. Billy, the third owner of the horse and explained everything to Mia. He told her that the horse is not thin but it is ill and it is in its last stage. After this meet they both have became friends. Connor, Mia’s mother’s boyfriend, while preparing the tea in the kitchen, interacted with Mia regarding the music video that Mia was watching. Connor works as the security guard in the hardware store and wanted to be a father figure for the two children.Connor always carries Mia to her room and also removes shoes and put blanket on her. Mia’s mother, Joanne, was enthusiastic as when she asked for the trip, both of the girls got ready to attend her mother and Tyler had shown much interest. When they were on trip, Connor asked about the animal and played the songs of California Dreaming. Mia always tried to impress Connor as when he was catching fish she helped him and also when her mother got hurt in the river, Connor avoided Joanne to give a piggy-back ride to Mia.Mia was slowly attracting towards Connor and she was having some thought in her mind related to Connor. She reacts angrily with the Connor and due to which Connor came to know that she is the witness of the intercourse between him and Mia’s mother. Connor borrowed the camera and gave that to Mia as she wants to go for the auditions of the local dance. In between that time Mia came across the social worker who was introduced by her mother to restart her schooling which she had left. But Mia refused to go and had a drink from kitchen and went out of house.She had seen the video on street dancing on YouTube and took the help of Billy to search the car parts to buy the alcohol for her self. After she sent her video, sh e received the call for the audition. When they were celebrating by having the drink, Connor asked Mia to show her dance steps. She performed on California dreaming and was asked by Connor to sit along with him. As Joanne went upstairs, Connor and Mia had sex and then he was embarrassed by the thing he had done with Mia. So he told her not to reveal the secret to Joanne.The very next day she came to know from her mother and Tyler that Connor had left and Mia knows the place where she can find Connor. Mia found him in his house in Tilbury and talked with him so he told her that he is unable to go back again to her mother which directly indicates that he doesn’t even want to meet Mia again. She didn’t made any issue of the age difference but Connor given her money before the goodbye kissing and left her to the station to get herself back home. She wasn’t ready to back her home but she again reached to the Connor’s home from the back window and entered into it as she found it empty.In Connor’s house, she came to know that Connor is married and also he’s having the daughter named, Keira and she had a call of nature over there on the floor. Mia then came out of the house and made a move but she have seen Keira playing on her scooter, also she convinced Keira to set off across the field along with her that she’ll give her an ice-cream as told by the Keira’s mother to Mia. Keira started kicking Mia as they were running through the field and approaching towards river. As Keira became upset, then she started troubling Mia, and as Mia got frustrated, she pushed her and Keira fallen down into the river.Then Mia saved Keira with the help of the Branch of the tree otherwise Keira might have drawn completely. After saving Keira, they both returned back towards the home as the Keira was wet and feeling cold too. Then in between their way to home, Connor arrived and slapped Mia and pushes back her. He then took Keira and drive back towards the home. Many days have been passed and then Mia came to the audition for which she had been called and seen the exotic dancer performing. Her turn came and she came on stage and music started.Then she had seen the fellow semi-nude auditionees and she walked off from the stage and went out to find Billy. She came to know that the horse which she cared for was dead and started weeping. Then Billy came and tried to stop her weeping and ask her to accompany him as he was leaving for Cardiff. Mia got ready and packed her bags and after having a dance with her mother and sister on the song â€Å"Life is a Bitch and then you die†, she went off. While she was leaving her mother didn’t reacted as she said good bye and then she sat with Billy and drive away for the new life.The movie is full of drama and sequence of events that keeps the interest of audiences. Mia in the Fish Tank is struggling with her own emotions, desires and issues of morality. The clim ax of the movie is a mixer of the feelings where in one hand she leaves the audition that was for erotic dancer, her favourite horse dies and she decides to move ahead to explore better opportunity and before that she enjoys with her family. Movie 2 Another movie which was also based on the same genre was â€Å"Nowhere Boy†. In this movie a teenage boy, Johnson, got success just because of his aunt and uncle.His aunt, Mimi, who is loving, inspirational and reserved kind of woman while her husband, George, is companion for the lively and intelligent boy. John was overwhelmed, when her uncle died due to cancer. During the funeral, John met his cousin Stan who showed him the place where his mother lives and was shocked that the house is nearby to his aunt’s and there he met Julia. Julia was fun loving girl whereas her aunt was strict. Julia’s clothes and her hair have the matching which work as the attraction for John towards Julia. The relationship became deeper b etween Julia and John which was unfair to Mimi.Julia teaches John to play Banjo and also introduced him to â€Å"Rock n Roll†. Mimi unknowingly bought a guitar for John and due to which he failed to improve in the school and was suspended. Then he moved along with Julia to her home where he met with Bobby. In that night he heard Julia and Bobby’s conversation with which he recognized that Julia is soft hearted and next day she again moved back to her aunt’s house. Then he met with the young guitarist who just looks like a twelve years old kid but he can play the guitar better than any other band.They started the rehearsals together and the band also started creating buzz. Soon he started getting fame and he enjoyed that. Then on Julia’s birthday, he met her after a long time span and found out the truth that why he got irritated in his life. And after that his life started moving smoothly and he got success to every point. The movie shows the struggle of the teenager to deal with the past and move ahead with life. The events and the presentation of events have been very impressive in entire movie.In both the movies, the main aspect was to show the life of the teenage girl and a boy that how the society deals with. In Fish Tank, Mia was the girl who got admired by the street dancers who were performing and in Nowhere Boy also, John got admired from the guitarist who can be able to play much better than the band. And in both the movies, director had shown clearly that the future is influenced by the past. So Mia got tensed in the movie Fish Tank as she heard that Connor had left them and in Nowhere Boy, John was also got irritated due to his past.These movies was generally built for the young generation people as they already have pressure of studies and their hobbies and what they want to be in their life. Society also provide pressure to them which result in making pressure in the mind of the child and due to this many children left studying and they got distracted from their hobbies too. Reference British Film Industry available at http://news. bbc. co. uk/2/hi/in_depth/entertainment/2003/british_film_industry/default. stm Curran and Porter, 1993 British Cinema History, London: Weidenfeld & Nicholson 9-23Murphy, R. ed. , 2009 The British Cinema Book, London: BFI, 1-64, 65-142 Fish Tank official website http://www. michaelfassbender. org/episodesfte. html http://www. hollywoodreporter. com/hr/film-reviews/fish-tank-film-review-1003973214. story Image Fish Tank from http://www. movieroar. com/images/fish-tankpster1. jpg Nowhere Boy Movie Review http://www. futuremovies. co. uk/review. asp? ID=1110 No Where Boy movie details available at http://www. nowhereboy. co. uk/ http://www. hollywoodreporter. com/hr/film-reviews/nowhere-boy-film-review-1004031851. story

E.T. Movie Released

The movie E.T.: The Extra-Terrestrial was a hit from the day it was released (June 11, 1982) and quickly became one of the most beloved movies of all time. The Plot The movie E.T.: The Extra-Terrestrial was about a 10-year-old boy, Elliott (played by Henry Thomas), who befriended a little, lost alien. Elliott named the alien E.T. and did his best to hide him from adults. Soon Elliotts two siblings, Gertie (played by Drew Barrymore) and Michael (played by Robert MacNaughton), discovered E.T.s existence and helped. The children tried to help E.T. construct a device so that he could phone home and thus hopefully become rescued from the planet he was accidentally left upon. During the time they spent together, Elliott and E.T. create such a strong bond that when E.T. started to become sick, so did Elliott. The plot got even sadder when agents from the government discovered the dying E.T. and quarantined him. Elliott, distraught by his friends illness, eventually rescues  his friend and flees  from the pursuing government agents. Realizing that E.T. would only really get better if he could go home, Elliott took E.T. to the spaceship that had returned for him. Knowing they would never see each other again, the two good friends say  goodbye. Creating E.T. They storyline of E.T. had its beginnings in director Steven Spielbergs own past. When Spielbergs parents divorced in 1960, Spielberg invented an imaginary alien to keep him company. Using the idea of a lovable alien, Spielberg worked with Melissa Mathison (future wife of Harrison Ford) on the set of Raiders of the Lost Ark to write the screenplay. With the screenplay written, Spielberg needed the right alien to play E.T. After spending $1.5 million, the E.T. we now know and love was created in multiple versions for close-ups, full-body shots, and animatronics. Reportedly, the look of E.T. was based on Albert Einstein, Carl Sandburg, and a pug dog. (Personally, I can definitely see the pug in E.T.) Spielberg filmed E.T. in two very unusual ways. First, nearly all of the movie was filmed from the eye-level of the children, with most of the adults in E.T. only seen from about the waist down. This perspective allowed even adult moviegoers to feel like a child while watching the movie. Secondly, the film was mostly shot in chronological order, which is not a common filmmaking practice. Spielberg chose to film this way so that the child actors would have a more realistic, emotional reaction to E.T. throughout the movie and especially during E.T.s departure at the end. E.T. Was a Hit E.T.: The Extra-Terrestrial was a blockbuster movie right from its release. Its opening weekend grossed $11.9 million and E.T. stayed at the top of the charts for over four months. At the time, it was the largest grossing movie ever made. E.T.: The Extra-Terrestrial was nominated for nine Academy Awards and won four of them: Sound Effects Editing, Visual Effects, Best Music (Original Score), and Best Sound (Best Picture that year went to Gandhi). E.T. touched the hearts of millions and has remained one of the best movies ever made.