Determining Avogadro’s Constant and Faraday’s Constant

Determining Avogadro’s Constant and Faraday’s Constant List of Apparatus Name of Apparatus Quantity Uncertainty Electronic Stopwatch 1  ±0.2s Ammeter 1  ±0.01A Wires with crocodile clips 1 D.C power source 1  ±0.01V 300cm3 Beaker 3 Copper strips 2 Sand paper 1 Graphite rod 2 pH probe/data-logger 1  ±0.2 Electronic weighing balance 1  ±0.001 DATA COLLECTION: The electrolytic cell used in this investigation is illustrated in Fig 1: Fig 1 Diagram of electrolytic cell used in investigation In this investigation, a current is passed through the solution with copper as the cathode and graphite as the anode. After a set amount of time, the circuit is disconnected and the mass of the cathode is measured. Following which, calculations are made so as to determine the Avogadro’s and Faraday’s constant. Qualitative Observations When the D.C power source was turned on, bubbles were formed at the Graphite anode. As the reaction progresses, powdery substance gets suspended in the solution and a black solid deposits can be found at the bottom of the beaker and there is a visible decomposition of the graphite electrode. As the reaction progress, a pink layer of copper forms on the copper strip. The copper strip is originally brown in colour while the graphite electrode is black in colour. Eventually, as the graphite electrode decomposes, the graphite molecules will turn the copper (II) sulphate solution from blue to black in colour. However, when the copper sulfate solution is filtered, it is noted that there is a decrease in the intensity of the blue colour in the filtrate after the electrolysis. The initial pH of the solution is 2.75, after the electrolysis is carried out, the pH decreases to 2.10. Data Collection Constant variables Time Interval/s( ±0.2) 300 Voltage/V 4V Current/A( ±0.01) 0.25 Cathode Trial 1 Initial mass/g ( ± 0.001 g) 1.315 Final mass/g ( ± 0.001 g) 1.279 Change in mass/g ( ± 0.002 g) 0.036 Chemical equation for reaction at the anode: 2H2O (l) à ¯Ã†â€™Ã‚  O2 (g) + 4H+ + 4e (aq) Chemical equation for reaction at the cathode: Cu2+ (aq) + 2e à ¯Ã†â€™Ã‚   Cu (s) Calculations for cathode Calculations Error Propagation Change in mass(Cu) = 0.036g Mols of (Cu) = =5.7 x 10-4 mol Number of mol of electrons- Using mol ratio Cu2+ (aq) + 2e à ¯Ã†â€™Ã‚   Cu (s) Number of mol of electrons =11.4 x 10-4 Charge flowing through circuit Number of electron charges in circut= Where is the elementary charge, the charge of one electron Number of electron charges in circuit = Number of mol of electrons Where L is the Avagandro’s constant Equating the number of mols of electrons obtained form the copper mass data and the number of mol of electrons from the current- Faraday’s constant = = 67000 C % ±ÃŽâ€ Mol of Cu = % ±ÃŽâ€ Mol of Cu = = 5.6 % % Uncertainty of number of mol of electrons = % uncertainty of Mass(Cu) =5.6% % uncertainty of number of mol of electrons =5.6% % ±ÃŽâ€ charge flowing in circuit = Percentage error Percentage error for Faraday’s Constant = = = 30% Percentage uncertainty of faraday’s constant =5.9% Percentage systematic error in Faradays’ constant =%error-%random error = 24.1% Percentage error for Avogadro’s Constant = = 30% Percentage uncertainty of Avogadro’s Constant =5.9% Percentage systematic error in Avogadro’s Constant =%error-%random error = 24.1% Conclusion In conclusion, the calculated value of Faraday’s constant is mol-1 and Avogadro’s constant is. As seen above, the percentage error for both Faraday’s constant and Avogadro’s constant are both 30% and after subtracting the error due to instrumental uncertainty, the % systematic error obtained is 24.1%. This shows that the experimental values calculated differ greatly from the literature values, indicating that there has been a significant amount of systematic error, which has caused the calculated value to be much different from the literature value. As percentage error of both Faraday’s constant and Avogadro’s constant are much larger than their respective percentage uncertainties, this indicates that the sources of systematic error are significant and cannot be ignored Evaluation Type of error Limitation Improvement Systematic Oxidation of copper occurs naturally when the copper strip is exposed to oxygen and when it is heated in the oven. Even when sand paper is used to scratch off the layer of copper oxide on the surface of the, it is difficult to completely rid of all the copper oxide. The formation of copper oxide will affect the reaction when electrolysis occurs and will affect the change in mass of the copper electrode, which is the dependent variable in this experiment. Even when the copper strip is immersed in the copper (II) sulphate solution, after a period of time, it will eventually start to form a layer of copper (II) oxide which will not be involved in the electrolysis reaction. This will reduce the amount of copper which will undergo reaction, causing it to reduce the eventual calculated Faraday’s and Avogadro’s constant. It is impossible to prevent the oxidation of copper from happening however, this systematic error can be minimised. Other than ensuring that the layer of copper oxide is scratched off by rubbing the copper strip excessively with sandpaper. The time for which the copper stays in the oven can be minimised or hair dryer can be used instead to blow the water off. Systematic When the graphite electrode starts to disintegrates as the reaction progresses, fragments of graphite will be dispersed throughout the entire solution. As copper (II) ions move towards the copper strip to plate it, some of the graphite fragments may end up attached to the copper strip as well and are unable to fall off as a layer of copper plates over the graphite fragments. This can be observed in the experiment when the copper strip is removed at the end of the experiment; black fragments of graphite are observed on the copper strip. The graphite fragments would easily reach the copper strip mainly because they were quite near each other. Hence, the graphite fragments could easily move towards the copper strips and attach to them. In order to minimise this from happening, the experiment should be conducting in a 500cm3 beaker, with the copper strip and the graphite electrode held further away from each other. Also, the graphite electrode should be positioned below the copper strip so that as the graphite electrode disintegrates, the graphite fragments will simply sink towards the bottom of the beaker, hence it will be less likely for the graphite fragments to accidentally coat onto the copper electrode Systematic Fluctuations in the current. Whenever the 2 electrodes were moved, the current of the circuit changes. Hence, whenever the copper electrode was moved in order to be weighed, the current would fluctuate, resulting in an inconsistent current throughout the experiment. If the current deviates from the stated 0.25, the resulting Faraday’s constant and Avogadro’s constant will be affected as well. An increase in current will result in an increase in the Faraday’s constant and Avogadro’s constant calculated while a decrease in current will result in a decrease in the Faraday’s constant and Avogadro’s constant calculated. In order to prevent fluctuations in the current as a result of the shifting electrodes, a retort stand can be used to hold the electrodes in place and prevent them from moving. This is much more reliable than just using hands to hold the electrode, resulting in a reduction in the fluctuation of the current A rheostat can be used and included in the circuit in order to adjust the amount of resistance of the circuit so that the desired current can be achieved. As current is inversely proportionate to resistance according to Ohm’s law, the resistance of the circuit can be adjusted in order to ensure a consistent current of 0.3 throughout the experiment. Systematic Also, another source of systematic error in this experiment would come from the fact that, the reading on the ammeter does not indicate the actual electric current flowing through the electrodes and the electrolyte as this value may decrease due to power losses in the wires. That is the electrical energy would be converted to heat. However the resistance of the wires in the circuit was assumed to be negligible in this experiment for simplicity. This would lead to systematic error as we would consistently overestimate the magnitude of the current flowing through the electrolyte. This error can be avoided if the values of the resistance of the wires as well as the internal resistance of the power source were known and included in the calculations made. Systematic The copper electrode may undergo a process called passivation[1] where the metal forms a protective layer on its surface to protect it from outer factors such as water or air to prevent corrosion. Such a protective layer will result in a high resistance which will lead to a voltage delay. This process may also occur on the graphite electrode. During the reaction, in the presence of passivation, the initial rate of the increase in mass of the copper electrode will be slowed down; ultimately affecting the total gain in mass by the copper electrode, affecting the Faraday’s constant and Avogadro’s constant calculated. This process of passivation can be removed by allowing the reaction to progress for 5 minutes to avoid a voltage delay. 5 minutes was chosen because too short a time will be insufficient to remove the protective layer on the electrode and too long a time will result in the disintegration of the graphite electrode even before the collection of data has begun. As mentioned above, if there is too much graphite fragments in the copper (II) sulphate solution, they may come into contact with the copper electrode and affect its final mass as copper ions plate over the graphite fragments on the copper electrode. Random Error Due to time constrains, only one set of data was collected. This will result in the fluctuation of the value of the Faraday’s and Avogadro’s constant. In order to reduce the error, perhaps more sets of data can be collected, so that a graph of metal deposited against time can be plotted and the gradient will enable the determination of the two constants. [1] Metal passivation-en.w,wikepedia.org/Passivation_(Chemistry). Accessed- 26/2/2014)

Media Control Essay -- Argumentative Persuasive TV Ads Essays

Media Control In the United States, most of us probably feel that we live in a relatively free environment. We are proud to live in a country in which we are supposedly given the freedom of choice. We are proud of our freedom to voice our opinions. We feel no pressure to conform, but we do every day in ways that we are completely unaware of. We are oblivious to the messages we are constantly receiving from the media, messages that tell us how we should think, feel, and act, and this oblivion makes us all the more vulnerable. In the U.S., the average person sees 25,000 commercials a year. These commercials are not just advertising a product. They are also advertising the values and lifestyles that surround it. Take, for example, our countries burst of patriotism after the September 11th attacks. Soon after the attacks, the cover model of Vogue appeared on the November issue wearing an American flag T-shirt, and a page of the magazine was dedicated to advertising the new style of â€Å"chic, patriotic† clothing. Television commercials as well have taken a turn towards patriotism, some in very subtle ways. It seems that many ads now emphasize families, comfort, sentimentality, and security, things that are desired by many U.S. citizens after the attacks. Through indirect messages, ads not only promise these things to those who purchase their products, they also promote these desires and feelings, wrapping us all up in warm, patriotic comfort instead of encouraging any kind of critical thinking or exa mination of the issue at hand. Few of us are safe exempt from receiving these messages, as 98% of all homes in America own a TV set, and the average person spends four hours a day watching it. Unfortunately, it isn’t just the c... ...dcasters, which is paramount†. By law television broadcasters are obligated to â€Å"serve the public interest, convenience, and necessity† and broadcast programs that inform communities on local, national, and global issues from diverse perspectives. The ideal media would reflect the interest of the entire population, not just an elite few. There are already many independent news sources though they reach a significantly smaller audience than the mainstream media. If we could turn the media so that it works for the people it could be an amazingly useful tool for informing and educating the public on vitally important issues that do not currently receive enough attention. As Lester Brown, author of the State of the World book series says, â€Å"The communications industry is the only instrument that has the capacity to educate on a scale that is needed in the time available.†

Analysis of Trifles by Susan Glaspell Essay -- Susan Glaspell

"Trifles" is a play with a unified plot. Although there are verbal flashbacks to the events of the day of the murder of John Wright, the play's entire plot begins and ends in a span of one day. The author also extends the unified plot to create a single setting (the farmhouse kitchen). The plot centers on John Wright's murder. Mrs. Wright is the main suspect; an investigation is taking place as to the motive or reason for the crime. The Sheriff, Mr. Hale and the County Attorney are introduced first to the audience. They are investigating the crime scene. The women, Mrs. Hale and Mrs. Peters, accompany the men to gather whatever of Mrs. Wright's belongings that she needs in jail. This exposition turns ironic when the women end up "investigating" and actually come up with evidence, while the professional men leave without an answer to their quest to find a motive for the murder of Mrs. Wright's husband. Mr. Hale gives an account of what he came upon the day of the murder. He found Mrs. Wright in a state of shock and nervousness. Mr. Hale states that Mr. Wright didn't care much for talking to people; all he wanted was peace and quiet. This foreshadowing will be used by the women, mainly Mrs. Hale, to connect the motive to the dead bird that they find later on in the play. Additional foreshadowing facts are the broken jelly jar and the "very cold" kitchen atmosphere. Again, the women feel that this coldness was what drove Mrs.' Wright to murder. Mrs. Hale informs the County Attorney that Mr. Wright was not a very cheerful man, which may be why the farmhouse does not look or feel cheery. The audience learns that Mr. Wright was a cold, uncommunicative, selfish man. The theme of men versus women come into view... ...ver, Mrs. Peters undergoes character development from believing that it should be up to the law to decide what should happen to Mrs. Wright to being convinced that women ought to stand together against the stereotypical views of women that the men have. This change occurs when Mrs. Peters recalls a childhood event that involved her cat and a mean, dreadful little boy. The play's rising action occurs at the point when the men could not connect the why and the how of John Wright's murder. The women, as they meddle with their "trifles", uncovers the knowledge and objects that the masculine detectives were seeking. In the end, the men come up empty and the women leave the farmhouse with concealed evidence in hand - the dead bird. The audience is left thinking that Mrs. Wright will be a free woman. As to what the actual verdict will be, no one knows.

God’s Responsibility for the Fall of Man

God’s Responsibility For The Fall Of Man Within Literature, an unofficial definition for human wrongdoing has been connected to Adam and Eve’s expulsion from Eden. Their incompetence of following God’s orders, resulting in the punishment of mankind, has been thoroughly outlined within the text of the Bible. Yet are their actions truly of their own? God’s inept decision creating man within his image and His disdain leadership left human beings in a inferior position to disobey his orders, leaving him solely to blame for their ignorant actions.The power of leadership is a critical factor that even figures of immortal stature need to practice. God’s first mistake leading to the fall of man lies within decisions to create an entity upon the earth similar to him. â€Å"And God created the human in his image, in the image of God He created him, male and female He created them† (Simon 98). Why would someone create a figure of life within his own lik eness without giving them the same amount of freedom?Regardless of his position as the ultimate Creator, the expectations set within creating life forms with authoritative intentions similar to his own leaves God’s image as a wise leader questionable. His kind nature may have been proposed as good intentions, but the lack of decisive decision-making leaves him exposed to lacking thorough process for leadership. Another essential factor of successful leadership is to be supported by followers who believe in their leader.Adam & Eve’s actions within the Garden of Eden are more appropriately noted as a poor lack of leadership then a story of betrayal and self-disobedience. Within chapters 1-3 of Genesis, the persuasive words of the Snake easily motivate Eve to break God’s command and strive to eat the forbidden fruit. â€Å"For God knows that on the day you eat of it your eyes will be opened and you will become as gods knowing good and evil† (Simon 99). If Go d’s leadership was sufficient enough, how could this even take place?God’s insufficient leadership over his creations allowed Adam & Eve to be easily swayed by the leadership of an animal which he placed them in power to control. This is confirmed in later chapters of Genesis 6-9 where he makes the ultimate decision to dispose of all things he gave life to. â€Å" I will wipe out the human race I created from the face of the earth, from human to cattle to crawling thing to the fowl of the heavens, for I regret that I have made them† (Simon 101).For a leader to dispose and restart his initial intentions due to regret shows that mistakes have been made by that individual. And God’s decision to do so emulates that the fall of mankind was not of his subjects, but of his own disdain leadership skills. In conclusion, God’s poor decision making led to the evident fall of mankind. His actions were that of a leader who had well intentions, but had a poor pe rception of his follower’s involvement to his leadership. If he were more methodic in his decision making, he would of never regretted his choices made during the seven days of creation.

Difference between monopoly pricing and competitive rricing Essay

Essay #1 – Congress is discussing the possibility of removing patent protection for life saving drugs in order to reduce the cost of the Medicare and Medicaid systems. Discuss both the short-run and long-run implications for the economic situation of the drug industry. Include in your answer the impact on prices, new development, etc. of drugs. Include appropriate graphs showing the difference between monopoly pricing and competitive pricing. The drug industry currently takes on both monopolistic and competitive market structures. When a drug company develops a new drug, there are patent laws that allow the company to have a monopoly on selling the drug. In the short-run, the company is able to charge the monopoly price (above marginal cost) and maximize profit by producing the quantity where marginal revenue equals marginal cost. Once the patent runs out, other drug companies have an incentive to enter the market causing it to become more competitive. These new companies produce generic versions of the drug and charge a price below the monopolist’s price. As more and more competitors enter the price is driven down to marginal cost. If congress were to remove patent protection on life-savings drugs, drug company’s profits for life saving drugs would decrease. More companies would be able to begin producing the drugs without waiting for the patent period to end therefore, the original drug maker would not be able to charge the monopoly price for very long because competitors could quickly engineer generic versions. The original producer would no longer be a price maker and instead need to follow profit maximization rules of a competitive market by producing the quantity where marginal revenue equals marginal cost and charge a price equal to marginal marginal revenue. Since the original drug maker will not be able to benefit from monopoly pricing during the patent period, there will be less incentive for them to create lifesaving drugs. A part of the benefit of higher profits during the monopoly period is the ability to recoup some of the research, develop, and testing costs of producing these drugs that the generic makers do not incur. Consumers on the other hand would benefit from competition in the market which prevents a single drug maker from dictating the market price of these newly developed lifesaving drugs.

Resume Sample for Pharmacy

Mr. Venkatesh Jangala Phone: +91 9985398963 Email: venky. [email  protected] com Date of Birth: 23 november 1987 Address: D. NO; 3-578(A),Undavalli centre, Tadepalli(post), Gunturdist – 522501. Languages Known: English, Hindi, Telugu Objective: To be a part of an organization where my skills are put to an optimal use and which offers scope for knowledge and growth. Educational Qualifications: |Year |Degree/Certificate |University/Board |Marks obtained | |2012 |Master’s of pharmacy(pharm. hemistry)* |BITS Pilani, |7. 33/10 | | | |Hyderabad Campus |(CGPA) | |2010 |Bachelor of pharmacy |ANU(Acharya nagarjuna university) |79. 5% | |2005 |Intermediate |Board of intermediate education,A.P |93% | |2003 |SSC |SSC board,Andhra pradesh |87. 5% | Experiences / Projects: ? 6 months of internship at Hindustan Life care Limited,Kerala Worked in clean room(class 10,000) and performed Validation studies on clean room cleaning procedure in Blood bad department M. Pharmacy: ? Project- 1: Drug interaction studies for newer anti- TB drug. Studying of the metabolic interactions of a newer anti TB drug with other rugs in wistar rats such as Glipizide(CYP2C9 enzyme substrate) Ketaconazole( CYP3A4 inhibitor) by analysing the change in drug levels in plasma using RP-HPLC ? Project-2:Bio analytical method validation of a newer anti-TB drug. Analytical method development of a newly synthesised anti-TB drug using RP-HPLC with plasma samples and validating the parameters such as accuracy,precision and stability etc.. , Mini project(s) ? Pharmacophore modelling of adenosine receptor antagonists in alcohol addiction induced liver fibrosis Design of controlled released tablet formulations of verapamil hydrichloride and their physical evaluation. Others: Isolation of Hesperidin from citrus sinuses,and evaluation of hypo- glyceamic activity Hypo- lipidemic activity on rats . Technical Skills: ? Handling of HPLC, UV,FT-IR &dissolution apparatus ? Designing of Analytical and bio-a nalytical method development studies for newer drugs using HPLC and validation of analytical methods and instruments. ? Pharmacokinetic studies for a new formulation and drug. Documentation work in industries, design of quality assurance studies. Elective Courses: – Computer aided drug design. – Dosage form design Awards / Honours / Achievements: Published one paper on† Synthesis of highly potent novel anti-tubercular isoniazid analogues with preliminary pharmacokinetic evaluation† in Bio-organic and medicinal chemistry letters. Qualified GPAT & NIPER-2010. Extra-Curricular Activities: Organisation and participation in my B. pharm college. Won second prize in dancing competition held at my college

Movie Review: Journey to Justice

Movie Review: Journey to Justice â€Å"Journey to Justice† is a documentary about the issue of civil rights in Canada during the twentieth century. It focuses on the role of central people who took vital actions to end the issue of racial discrimination. The movie clearly portrays the experiences of black Canadians thorough interviews of key persons including Ray Lewis, Fred Christy, Stanley Grizzle, and Viola Desmond. Throughout the twentieth century, key players in the black community continued to fight for their rights despite serious discrimination. Firstly, Ray Lewis was denied the job as a coach after he won a bronze medal in 1932 Olympics because he was Black, and had to satisfy himself with the job of a porter. Secondly, Fred Christy, who was refused to be served in a bar, took the matter to Supreme Court. However, the court ruled the matter against him and rhetorically, made racial discrimination legal. Thirdly, Stanley Grizzle was forced be a batman and a washroom cleaner when he joined the army during the second world war, until he fought for his rights with his commanding officer. This time however, he won and served as one of the best officers in the Canadian army. Moreover, when Hugh Brunette came to Dresden with his two American friends, he was not served in a restaurant, while his friends were. After this incident he created an organization called National Unity Organization to fight discrimination. In 1947, he challenged the local government to pass an equality law, which was passed on to the provincial government for voting, where the restaurant owner-a white, won the case once again. This created a controversy and the premier and a group of other minorities took this case to a higher level until the equality law was passed in 1950s. Lastly, Donald Willard, an immigrant fought with the government for three decades along with Negro Citizenship association and the Labour congress of Canada to change the way in which they accept immigrants. He argued that using racial origin in accepting immigrants to Canada is unlawful and stated that they should be viewed according to their education, skills and work experience and won the case. This case played an important role in making it one of the most culturally diverse countries in the world. The point that the movie is trying to make is that issues cannot be solved if they are simply accepted. If no one stands up to fight for it as it the issue will continue to become more tense leading to even more serious effects. As in the movie, the issue of racism continued to worsen until some key people stood up to fight against racial discrimination of the Blacks. Finally, in the end they got the desired results. Not only were they able to pass a law stating discrimination is illegal, but they were also able to change the way in which immigrants were accepted to Canada. The contribution of Blacks, particularly Donald Willard, changed the way in which Canada is viewed – â€Å"The land of opportunities. † The movie is related to world issues in many ways. Firstly, it provides useful information in understanding the foundation of the issue of discrimination. Racism is an issue that is making headlines these days. For example, the rising resettlement against immigrants in Quebec and the war on terrorism, which is taking hundreds of lives today had it basis in racism. Many individuals from Islamic countries are questioned heavily by officials at American Airports after the terrorist attacks. Secondly, it openly reveals the hidden truths of the Canadian government and its political system including the Supreme Court which itself promoted racism by favouring the whites regardless of the issue or the case. These days political corruption is a major issue in developing nation particularly in south Asia and many part of Africa. Thirdly, this movie portrays the issue of Canadian Civil Rights movement, which is a movement that only a few Canadian are aware of. This movement is directly related to human rights – a growing issue in Asian countries today. Low-caste children all over Asia, more particularly India are forced to do child labour, similar to how blacks were forced to work on the rail road a century ago. Blacks were not given any other jobs because of their race and these children are deprived from education and proper jobs because of their caste. It is amazing, to see these countries making the same mistake that Canada made a few decades ago. Lastly, this movie touches on the issue of stereotyping. Even though it is not a big issue, individuals throughout the world use stereotyping to judge others, often in a negative way. This creates larger gaps between races. Even though the movie shows us that the issue of racial discrimination has ended, it still exists. It is true that the magnitude and seriousness of racism has declined but many groups of people suffer from bullying because of their race and ethnicity. For example, many â€Å"Brown† and â€Å"Asian† people are regarded as immigrants and are the victims of bullying in both schools only because they cannot quickly assimilate into the western society. ( Weakness of argument