Sunday, October 27, 2019
Reactions of Copper and Percent Yield
Reactions of Copper and Percent Yield Purpose-The purpose of this experiment is to examine the chemistry of copper and with the concept of percent yield. /2 Procedure- CHEM16882, Applied Chemistry1 Laboratory Manual Experiment no.6 posted on slate/Sheridan college, Brampton (accessed on 20.feb.2017) (1). /2 Observations Create your own data table for quantitative data. The table must include all the measurements you recorded in the laboratory; it must have a table number and title. Answer- Table for quantitative data measured while conducting the experiment. Compound Mass(+ /- 0.0001g) Initial weight of copper 0.5189g Final weight of copper 0.5651g Weight of 250 ml empty beaker 117.29g Evaporating dish 56.2529g Final weight of copper + evaporating dish 56.8180g /4 In table format record qualitative observations for each of the five reactions. All observations must be written in complete sentences. The table(s) must have a table number and title. Answer-Table 1. Reaction 1. Cu + Physical state The physical state of copper is solid. The physical state of Nitric acid is liquid. Copper2 nitrate is liquid in nature. Nitrogen dioxide is a gas. Water i.e. dihydrogen monoxide O ) is a Liquid. Color The color of copper is brown Nitric acid is clear. Copper 2 nitrate is in Blue green color. Nitrogen dioxide is in brownish shade Dihydrogen monoxide is Clear. ADDITIONAL OBSERVATION-Heat is generated during this experiment. Table 2. Reaction 2. Cu Physical state The physical state of copper nitrate is Liquid. The physical state of sodium hydroxide is Liquid. Copper hydroxide is Solid in nature. Sodium nitrate is in Liquid form. Color It is in Blue green color. It is Clear. It is Black in color. It is in Dark blue color. ADDITIONAL OBSERVATION-Blue precipitates are formed when NaOH is added. Table 3. Reaction3. Cu Physical state The physical state of copper hydroxide is Solid. Copper hydroxide is Solid. The physical state of dihydrogen monoxide is Solid. Color It is Dark blue in color. It is in Black color. Table 4. Reaction 4. CuO + Physical state The physical state of copper hydroxide is solid. Sulphur acid is in Liquid form. Copper hydroxide is liquid. The physical state of dihydrogen monoxide is Solid. Color It is in Blackish tone. It is Colorless. It is Light blue in color. Table 5. Reaction 5. Cu Physical state The physical state of copper sulphate is Liquid. Zinc is a Solid. Zinc sulphate is solid in nature. Copper is in Solid form. Color It is Black in color. It is Silver in color. It is Colorless. It is Reddish/brown in color. ADDITIONAL OBSERVATION-Heat is generated during this reaction. Write balanced chemical equations for each of the five reactions. Identify and name the product(s) for each reaction. State whether the product is a solid, liquid or gas. Answer-Reaction 1 Reaction 2 Reaction 3 Reaction 4 Reaction 5 /5 For each of the five reactions, identify the type(s) of reaction each is. Your choices are: decomposition reaction, oxidation-reduction reaction, acid-base reaction, combustion reaction, single displacement reaction, double displacement reaction and synthesis reaction. Answer- Reaction 1. It is a decomposition reaction. Reaction 2. It is a double displacement reaction. Reaction 3. It is single displacement reaction. Reaction 4. It is Acid Base Reaction. Reaction 5. It is a Redox Reaction i.e. oxidation reduction reaction because zinc loses 2 of its electrons and copper gains 2 electrons. /3 Calculations All calculations must show the equation used (typed with equation editor), units must be present with all numbers and the final answer must be recorded with the correct number of significant figures. 1. Calculate the % yield of Cu at the end of the five reaction steps. (This could also be referred to as the % recovery of Cu.) Show ALL calculations. Answer- Actual mass of copper=0.5189g Final mass of copper obtained= Mass of evaporating dish and copper (g) Mass of empty flat evaporating dish(g) =56.8180g-56.2529g=0.5651g=0.56g Percentage yield %= = /3 2. For Reaction 1 between Cu and HNO3, calculate the theoretical yield of Cu(NO3)2 in grams. Answer- Reaction 1. Molecular mass of Cu =63.546g/mol Molecular mass of HN=63.01284g/mol Molecular mass of =187.554g/mol Mole of Cu = Theoretical yield of = /3 3. For Reaction 1 between Cu and HNO3, confirm that HNO3 was present in excess. (Show a calculation to support your answer) Answer- Reaction 1. Molecular mass of Cu =63.546g/mol Molecular mass of HN=63.01284g/mol Molecular mass of =187.554g/mol Mole of Cu = Theoretical yield of = /2 4. For Reaction 2, calculate how many moles of NaOH you added. Answer- Reaction 2 Molecular mass of =187.54g/mol Mole of NaOH=1.4g /2 Questions What compound was being removed in the procedural step where 150 mL of hot R.O. water was added to the solid CuO precipitate? Do you think that all of this compound was removed by this washing? How could this error affect your percent yield? How could this error be minimized? Answer-Hydroxide atoms was being removed in the step of procedure where 150 ml hot water was added to CuO solid precipitate. No, I dont think so that all of compound was taken off by washing it. Some particles were added by human error, which resulted in increased amount of the product which affected the final result i.e. percent yield of copper. The chances of error can be reduced by various methods. One such method is by making some changes in procedure i.e. washing of precipitates entirely until the particles are removed thoroughly or by increasing dissolution process. /6 2. List two errors that could increase your % yield and two errors that could decrease % yield. Describe one of each type in details. Answer Two errors that may occur during conducting the experiment which could increase the % yield of copper are as follows-: By human error, i.e. while washing method some of the water cannot be removed from NaNO3 particles from copper hydroxide particles which will result in increased mass of final product. In the final result we got more mass than the actual mass because zinc does not fully react with CuSO4. Some particles still remain inside with the copper. Two errors that may occur during the experiment which could decrease %yield are as follows-: Some particles remain left inside the beaker while transferring from one to another which reduced the weight resulted in %yield. Some particles get transferred into the beaker with water and there was loss in the weight which affected the result and we get more mass than actual mass value. /8 Conclusion(s) /3 To sum up, the final mass of copper which is obtained after performing the experiment was greater than the initial copper mass. Reference(s) 1.https://slate.sheridancollege.ca/d2l/le/content/348286/viewContent/5357151/View (accessed on 20.feb.2017) 2. AC1 Experiment 6/Template_Copper Percent Yield, Ques 2. /2 Teacher Evaluation (Students leave this part blank) Overall organization of lab report: formatting of chemical and mathematical equations; clarity of answers; spelling and grammar; attention to details; completed cover sheet; use of headers and footers. Laboratory performance: punctuality; time management; team work; attention to safety; use of personal protection equipment; using appropriate lab techniques; preparation of lab data book in advance of the lab; cleanup of lab work area. /5 Total laboratory grade: /55 Professors suggestions for improvement:
Friday, October 25, 2019
China :: essays research papers
     China, (People's Republic of China), is situated in eastern Asia, bounded by the Pacific in the east. The third largest country in the world, next to Canada and Russia, it has an area of 9.6 million square kilometers, or one-fifteenth of the world's land mass. It begins from the confluence of the Heilong and Wusuli rivers in the east to the Pamirs west of Wuqia County in Xinjiang Uygur Autonomous Region in the west, about 5,200 kilometers apart; and from the midstream of the Heilong River north of Mohe in the north to the southernmost island Zengmu'ansha in the South China Sea about 5,500 kilometers apart.           CLIMATE: China lies mainly in the northern temperate zone under the influence of monsoon. From September and October to March and April next year monsoon blow from Siberia and the Mongolia Plateau into China and decrease in force as it goes southward, causing dry and cold winter in the country and a temperature difference of 40 degree between the north and south. POPULATION: Total Population 1.2591 billion (1999) about 22% of total population in the world. Year     Total Population     Urban Population     Rural Population 1995     1.2112 billion          1996     1.2239 billion     359.5 million (29.4%)     864.39 million (70.6%) 1997     1.2363 billion     369.89 million (29.9%)     866.37 million (70.1%) 1998     1.2481 billion          1999     1.2591 billion     388.92 million (30.9%)     870.17 million (69.1%) 2000     1.29533 billion     36%     64%      Country name:     conventional long form: People's Republic of China conventional short form: China local long form: Zhonghua Renmin Gongheguo local short form: Zhong Guo abbreviation: PRC Government type:     Communist state Capital:     Beijing Administrative divisions:     23 provinces (sheng, singular and plural), 5 autonomous regions* (zizhiqu, singular and plural), and 4 municipalities** (shi, singular and plural); Anhui, Beijing**, Chongqing**, Fujian, Gansu, Guangdong, Guangxi*, Guizhou, Hainan, Hebei, Heilongjiang, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Jilin, Liaoning, Nei Mongol*, Ningxia*, Qinghai, Shaanxi, Shandong, Shanghai**, Shanxi, Sichuan, Tianjin**, Xinjiang*, Xizang* (Tibet), Yunnan, Zhejiang; note - China considers Taiwan its 23rd province; see separate entries for the special administrative regions of Hong Kong and Macau Independence:     221 BC (unification under the Qin or Ch'in Dynasty 221 BC; Qing or Ch'ing Dynasty replaced by the Republic on 12 February 1912; People's Republic established 1 October 1949)
Thursday, October 24, 2019
Merck Executive Summary
EXECUTIVE SUMMARY Statement of the Problem Merck & Co. , Inc. , a leading pharmaceutical company, faces the threat of the patents of its most popular drugs expiring in 2002. The only way to counter the loss of sales from these drugs going off patent is to develop new drugs in order to refresh the company’s portfolio. LAB Pharmaceuticals, a small pharmaceutical company who specializes in the treatment of neurological disorders, has approached Merck with the opportunity to license Davanrik, a new drug with the potential to treat both depression and obesity. The drug is currently in pre-clinical development and would still need to pass a seven year and three phase testing process approved by the FDA. Under the licensing agreement, Merck would compensate LAB with an initial fee, milestone payments as the drug progresses through each phase, and royalty on sales. Merck must make a decision on whether or not to license the drug. If Merck does decide to license the drug, it must also decide how much the drug is worth. Discussion A decision will be madeusing both qualitative factors and quantitative analysis. Qualitatively, this opportunity is positive for both Merck and LAB. Licensing this drug will allow Merck to insert a newly patented compound into the market and to bypass the discovery and preclinical testing phases. By being able to skip those two phases, Merck can go straight to clinical testing saving it six to seven years, which helps Merck deal with its patent life cycle in a more effective manner. LAB has never had a drug successfully complete the FDA approval process in its 15-year history. Its stock price had also fallen by 30% after its most recent FDA denial. Therefore, by licensing this Davanrik to Merck, LAB would be able to receive some much-needed cash. A successful transaction between Merck and LAB could also lead to future opportunities. Quantitatively, a decision tree analysis was used to value this opportunity because as long as Merck only accepts projects with a positive expected value it will earn profits more often then lose money. Through the analysis of the expected value of each possible outcome, the expected value of licensing Davanrikfrom LAB is $13. 98 million including payments to LAB of $16. 68 million. Although the FDA approval process has a 40% Phase Iand a 70% Phase II failure rate, the cost f failing early on is only $30 million and $70 million, respectively, relative to the opportunity to earn as much as $1. 28 billion if successful. Recommendation Merck should license Davanrikfrom LAB for no more than $13. 98 million. The company is facedwith the risk of declining profits if new drugs are not developed since many of its patents are expiring soon. Therefore, it is necessary to invest in new drug developments. Als o, the expected value of $13. 98 million indicates that this opportunity is profitable and that Merck can receive up to $1. 28 billion by licensing the compound.
Tuesday, October 22, 2019
But its not Funny Essay Example
But its not Funny Essay Example But its not Funny Essay But its not Funny Essay Ai-ai Delas Alas, Pokwang, John Lapus, Pooh, Chokoleit, Ate Gay and many of the like, children in school, officemates and even professionals like doctors and lawyers use transgressive Jokes. People who look different from others by skin color, size, height and other deformities are vulnerable subjects of laughter. These Jokes affect peoples emotions, thus degrading their sense of self-worth and self-esteem and diminishing their self-confidence. However, despite the possible effects of continuous use of transgressive Jokes, many people, private or public still accept this kind of Jokes. Vice Gandas concert, I-Vice Ganda Moko sa Araneta last May 17, 2013 had a full- house in Smart Araneta Coliseum which had around 16, 500 seating capacity -a proof that people enjoy hearing this kind of Jokes -transgressive and obscene. One possible reason is that these transgressive insults are dressed as Jokes. Thus, the obvious effect involved in laughing at someone or something has been brought IoW or degraded (Purdie, 59). Ngipin palang dehado na! is what Vice Ganda exclaimed while holding on to a mans Jaw showing his deformed teeth to the screen (Gandang Gabi Vice). Afterwards, he hugged him and said, Joke lang kuya. Its an example of an insult dressed as a joke. In instances like these, people expect the subjects to not take it seriously because implicit transgression has been transmitted (Purdie, 13) from the comedian to the audience. Another thing is because Jokes are not held within the bounds of the law (Purdie, joke, it is no longer under the control of the law which is also one reason why bullies re never comprehended. Because of Jokes being not bounded by the law, comedians [use Jokes] to discharge sexual aggressive and other forbidden thoughts and fantasies without worrying about being punished (Strean xii). When Vice Ganda stated his Joke regarding gang rape about Jessica Soho, he knew the subject may or may not react to it but he still pursued the Joke. There is a probability that it is because he knew that it will be accepted by the people and that law wouldnt intervene. Many Filipinos think that to laugh is a must because of the saying, laughter is the best medicine. That is also why Jokes, though transgressive, are widely accepted by the Filipino public. People consider these Jokes opportunities to play, to regress, to depart from the demands of reality and to enjoy the child in ourselves and in others (Strean, 3). But what makes it funny? Delivery is a factor of every Jokes humor. Many comedians do not present the same joke all over again to the public. No one would watch GandangGabi Vice every Sunday if the same set of Jokes is to be expected from Vice Ganda. Many stand-up comedians as well, prepare a new set of Jokes every presentation and if ever a Joke would be epeated, there is quite a long interval in between. This contributes to the surprise factor of Jokes. It isnt a Joke without surprise (Strean 26). O! Instant sandok na Oh! Vice Ganda said referring to the man with a very long face (Its Showtime). Notice that the Joke mentioned above is Just a five- word Joke but it was able to gain so much laughter from the audience. Length is also a factor in creating good and funny Jokes. The longer the Joke, the longer time it is to process it increasing the risk of not being funny. Therefore, the shorter the Joke, the better. The effective use of metaphors -a comparison between two unrelated things- in Jokes is also a m ajor factor. Masarap talaga ang saging! Basta malaki , This sexual Joke is an example of a metaphoric comparison. Many comedians have a very creative way of using metaphors to transmit the humor to the audience. An effective use of this will make it easier for the audience to capture the thought of any joke. After all, it is all in the matter of skill of delivery (Purdie, 36). Despite the non-stop use of transgressive Jokes by comedians of different kinds, the Filipino eople still accept and enjoy their Jokes. Francisco, Butch. Remembering Dead Stars. Philippine Headline News Online. 1 November 2003. Web. 13 October 2013. . Purdie, Susan. Comedy : The mastery of Discourse / Susan Purdie. n. p: New York ; London : Harvester Wheatsheaf, 1993. , 1993. print. Sorell, Walter. Facets Of Comedy / By Walter Sorell. n. p: New York : Grosset Dunlap , [1972], 1972. Print. Strean, Herbert S. Jokes :Their Purpose And Meaning / Herbert S. Strean. n. p. : Northvale, NJ. : J, Aronson , C1993, 1993. pnnt
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