Saturday, January 25, 2020
Hydrated Copper Sulfate Formula
Hydrated Copper Sulfate Formula Aim The aim of the experiment was to determine the empirical formula of hydrated copper (II) sulphate(CuSO4Ã · xH2O)by experiment and to investigate the changes of copper (II) ions in solution. Introduction Copper is a d-block Transition metals, which are elements in Group 3-12 of the Periodic Table. It has the electronic structure 1s22s22p63s23p63d104s1, and can form complex formation (Chemguide, 2003). Complex ions are compounds having a central atom surrounded by other molecules called ligands, and these ligands can form dative covalent bonds to the central particle (Lister and Renshaw 2000). Lister and Renshaw (2000) further state that good ligands can displace poorer ligands from complexes, and the log of stability constants (logKc) can be used to measure the stability of complexes. The larger logKc, the more stable the complex (Lister and Renshaw, 2000). Most complexes are coloured since the movement of electrons between d orbitals will absorb a quanta of electromagnetic energy and the resulting energy gap is corresponding to frequencies of electromagnetic radiation in the visible region of the spectrum (Lister and Renshaw, 2000). Copper (II) sulphate has a considerable number of compounds, which have different degrees of hydration. Fishing (2009) points out that pentahydrate (CuSO4Ã · 5H2O) is bright blue due to the water of hydration and when heated, the blue copper sulphate can be dehydrated to a grey-white power called anhydrous salt. The structure can be seen in Figure 1. Two water molecules will be lost at 30? when heated, and two more are then lost at 110?, followed by the last one at 250? (Fishing, 2009). As stated by Chemguide (2003), the typical blue hexaaquacopper (II) ion- [Cu(H2O)6]2+ is the simplest form in solution. Forming stronger bonds than water molecules with the center particle (Cu2+), chloride ions can displace water molecules and form a yellow-green [CuCl4]2- (aq) whose value of logKc is 5.6 (Lister and Renshaw, 2000). Figure 2 shows the structure of the [CuCl4]2-. The reaction of hexaaquacopper (II) ions with chloride ions can be shown as: [Cu (H2O)6]2+(aq) + 4Cl-(aq) [CuCl4]2-(aq) + 6H2O(l) (Chemguide, 2003) When copper (II) sulphate solution reacts with ammonia, it has two separate stages. Chemguide (2003) suggests that in the first stage, a small amount of ammonia can lead to hydrogen ions being removed from the hexaaqua ion. As a result, a neutral complex is produced, which is a precipitate with a pale blue colour (Chemguide, 2003). The equation for this reaction can be written as: [Cu(H2O)6]2+(aq) + 2NH3(aq) ?[Cu(H2O)4(OH)2](aq) + 2NH4+(aq) (Chemguide, 2003) Chemguide (2003) further reports that when adding excess ammonia solution, the ammonia will replace four of the six water molecules from [Cu(H2O)6]2+, forming a deep blue [Cu(NH3)4(H2O)2]2+(aq). Its value of logKc is 13.2 (Lister and Renshaw, 2000). The reaction can be shown as: [Cu(H2O)6]2+(aq) + 4NH3(aq)?[Cu(NH3)4(H2O)2]2+(aq) + 4H2O(l) (Chemguide, 2003) Method The apparatus consisted of crucible, spatula, burner and tongs, electronic balance, desiccator and stand, as well as three conical flasks, and the chemicals included copper sulphate, concentrated hydrochloric acid and ammonia solution. The method of this experiment was divided into two parts. According to Lane (2009.a), the practical for determining the formula in part 1 was done as following steps, and all figures gained were corrected to two decimal places. To start with, the inside of the crucible was cleaned with a cloth. Subsequently, a paper clip was placed in the crucible. The crucible was then weighed and the weight was recorded. After that, using the electronic balance, 2.58g copper sulphate was added into the crucible. Before placing the crucible on the stand and heating, the burner was lit and placed under the stand. Using the paper clip, the crystals were stirred when heating. The change in colour was then noted. After that, using the tongs, the crucible was placed inside the desiccator to cool down. When cool down to room temperature, the crucible was reweighed and the procedures heating, cooling, and weighing were repeated until constant weight was recorded. Some water was added to the crucible at the end and the result was noted. In part 2, the steps making complex ions in solution can be shown below (Lane, 2009.b). At the beginning, some copper sulphate and water were put into three conical flasks and these flasks were shaken and observed. After that, using a pipette, concentrated hydrochloric acid was dropped into one flask. Any phenomena were noted. Before observing, a small amount of ammonia solution was then added into the second flask. At the end, excessive ammonia solution was put into the third flask and the result was recorded. Discussion: In part 1, using the data from Table 1 and the formula n = m/Mr, where n = moles, m = Mass of sample and Mr = relative Molecular Mass (Lane, 2009.b), the steps in the calculation of the formula (CuSO4Ã · x H2O) can be shown as follows. Mr (CuSO4) =159.6 m (CuSO4) =1.64g n (CuSO4) = m/Mr =1.64/159.6 = 0.010289 moles Mr (H2O) = 18 m (H2O) = 0.94g n (x H2O) = m/Mr = 0.94/18 = 0.052222 moles The ratio can be determined: CuSO4: x H2O = n (CuSO4): n (x H2O) Therefore: 1 : x = 0.010289 : 0.052222 x = 5.0755 The value x = 5.0755 can be approximate to x = 5; therefore, the empirical formula is CuSO4Ã · 5H2O. As stated by theory, when heating the crystals, the water will evaporate depending on the temperature. Repeating heating and stirring the crystals can ensure the hydrated CuSO4 is dehydrated completely. The positive result of x = 5 indicates that the heater can reach 250? at least in the experiment, which provides the power to drive off all water molecules from the crystal. Copper (II) oxide (CuO) and sulfur trioxide (SO3) will be produced when heating the crystal at around 600? (Fishing, 2009). It can be deduced that when over heating, the black CuO (s) and the pungent smell SO3 (g) would be observed. The colour changing grey-white to blue when adding water into anhydrous copper sulphate can explain why the crucible needs to cool down inside the desiccator. It is to avoid the anhydrous copper sulphate absorbing H2O from the air and reforming hydrated CuSO4. This is also why anhydrous CuSO4 can be widely used for testing the presence of water in other chemical experiments. The green colour in part 2 could be explained in terms of a mixture of colours from [Cu(H2O)6]2+ (blue) and [CuCl4]2- (yellow-green). It can be deduced that if adding enough water into the green solution, the green solution would turn back to blue, because a high concentration of H2O would lead to the reversible reaction tending to produce more [Cu(H2O)6]2+. The results about copper (II) ions reacting with NH3 (aq) mean that the blue precipitate (Cu(OH)2) can dissolve when adding excessive of ammonia. All reactions tend to high stability, low energy. As mentioned by theory, the logKc value of [Cu(NH3)4 (H2O)2]2+ (aq) (13.2) is larger than [CuCl4]2-(aq) (5.6), which means that the complex [Cu(NH3)4 (H2O)2]2+ is more stable than [CuCl4]2-, and NH3 is a better ligant than Cl-. Therefore, the reaction NH3 replacing Cl- from [CuCl4]2-(aq) can be deduced. Compared with the empirical formula CuSO4Ã · 5H2O, the calculated answer is slightly high, although it can be estimated to x = 5. There are three main reasons can explain the result. The crucible may not be completely dry, and extra water evaporated will give a higher value. In addition, when over heating, the mass of gases would be regarded as the loss mass of water. Finally, some crystals would splash out when stirring, which can lead to the calculated value higher. In order to produce more accurate result, several areas could be improved. Controlling the flame intensity of burner, putting an asbestos net under the crucible or granulating the crystal can reduce the possibility of decomposition and ensure the crystal is dehydrated completely. Conclusion In conclusion, the empirical formula of hydrated copper sulphate can be determined as CuSO4Ã · 5H2O by experiment. Water molecules can make the copper complex ion blue. Ammonia (NH3) causes deep blue colour, and chloride ions (Cl-) make the copper complex solution yellow-green. Therefore, the nature of ligands can affect the energies of the d orbitals and produce complexes with different colours. References Chemguide (2003) [online] Copper Available at: http://www.chemguide.co.uk/inorganic/transition/copper.html [Access at: December 20, 2009] Fishing (2009) [online] Copper Sulfate, Equation for Decomposition Available at: http://www.finishing.com/116/07.shtml [Access at: December 22, 2009] Kecheng (nd) [online] Indentify the Formula of Hydrated Copper Sulphate Available at: http://kecheng.edu.people.com.cn/index/newscontent/snsy/czhx/syzl6_2_4_2.htm [Access at: December 28, 2009] Lane, R (2009.a) Chemistry Practical Handout Lane, R (2009.b) IFY Course Notes Lister, T. and Renshaw, J. (2000). Chemistry for Advanced Level (third edition). Cheltenham: Nelson Thornes Ltd.
Friday, January 17, 2020
Career Objective
The Purpose of Studying at AIT and Career Objective For Obtaining AITââ¬â¢s Master Degree I am a degree holder of Bachelor of Engineering (Information Technology) and I have a keen interest in information technology,especially in programming. During this years, I am not only working at Agricultural Mechnization Department as a Senior Assistant Engineer but also learning computer programming language. It has equipped me with stable technical skills in programming and experience with SDLC methodologies.Throughout the experience of working on different IT projects,it has established my interest in project management and I made me realized that my own career goal is to be a professional Computer Programmer or a Chief Information Officer. In our country ,many professional programmer and IT manager formed various committees and association such as Myanmar Computer Professional Association(MCPA) . The government has initiated various programs such as their Own Ministry Websites and the E -commerce system to provide strategic direction towards Myanmarââ¬â¢s IT development..However,these initiatives are facing issues such as lack of technology transfer due to short of IT specialists. However,I think that my existing knowledge and experience is insufficient for me to be able to achieve my goal. Hence , this is my motivation behind of my admission to your course. To be a successful Computer programmer and IT manager, rich IT knowledge and experience is critical. However,knowledge in various areas of project is also crucial.I expert that the Master in Computer Science at Asian Institute of Technology will allow me to enhance and strength my acamedic knowledge about management theories and programming methodologies. Also, through the peer to peer experience sharing to be able to familiarize myself with the challenges and difficulties that may arise during computer system management at various industries and learn how to overcome these challenges and difficulties by sha ring ideas with one another.I also strongly believe that my Master degree from AIT will give me the qualities and capability to help overcome the technology transfer obstacle in Myanmar. My graduate degree in AIT will help me become an IT specialist in the government office and in long term venture into technology management consultation to help Myanmar master the technology to compete with the developed countries that have moved on to a more advanced technology. I wish to form innovative strategies to initiate various database system ventures in the public sector.We must have built in every corner of the needs not only in economic, politic movement but also the basic communication and technology as well. We truly need the basic knowledge of 21 centuryââ¬â¢s general modern industrialââ¬â¢s beneficial and advantages. We must take the advantages of innovative technology in order to make some change for the better place of Myanmar. . The more we have variety educated, skillful an d professional social workers, and the better way to develop our country with respect to the basic needs.In my conclusion,today era is information and communication era. Todayââ¬â¢s youth will be able to catch up with the technological age only if they constantly study IT technologies in accord with the modern age. These are what I am willing to do and what I am always dreaming about how to make change for my country to be a democratic one. I truly believe that AIT is the best choice to due to the excellent academic reputation and atmosphere within the university. It will be great honor for me to have an opportunity to study a leading global university like AIT.
Thursday, January 9, 2020
A Primary Source Of The West Indies By Henry Nelson Coleridge
The document I chose to analyze as a primary source is Six Months in The West Indies by Henry Nelson Coleridge. This is a small journal published in 1825 that follows Henry N. Coleridgeââ¬â¢s trips around the West Indies with his uncle, William Hart Coleridge who is a bishop of Barbados. While on his trip throughout the isles, Coleridge not only comments on the local governments and ecosystems but the treatment of slaves and the institution of slavery as well. His viewpoints are in no way abolitionist, but he does appear to have a vein of sympathy for slaves of the West Indies. Many of his viewpoints are on how society and slave owners in the West Indies could better the lives of their slaves, none of them abolition, but for instance he suggests that ââ¬Å"one of the most effectual ways for bettering the slaves would be thorough and humanizing education of the masters themselves (p.54).â⬠While this argument, I feel, is not uncommon of a well-educated, English, relative of a high ranking religious official during this time period, I find it interesting to compare Coleridgeââ¬â¢s accounts of slavery throughout the West Indies with that of an actual slave, Mary Prince, in the same region. Mary Prince was a slave in the Caribbean, who was bought and sold to multiple owners, on multiple isles, eventually gaining her freedom in Britain in 1828. This secondary source, The History of Mary Prince, was transcribed by Suzanna Strickland and edited by the abolitionist who took her in, Thomas Pringle
Wednesday, January 1, 2020
Enlightenment Is Not True That Madness Before The...
How far is it true that madness before the enlightenment is understood in primarily religious terms? By Name Presented to Institution Instructor Course Date How far is it true that madness before the enlightenment is understood in primarily religious terms? Origin of Enlightenment During the enlightenment period, fact named itself in a manner that would later enlighten compatriots. The Enlightenment was one of rare movements in human history associated with 17th and 18th century. Scholars argue that it begun back primarily in Paris and London. This period was to see a great positive shift in tyranny, ignorance, superstition and to build a good reputation in the world(Macdonald, 1981). With this plan, the enlightenment had hereditary domination by aristocrats and religion as their sole targets. The logic behind the Enlightenment period is all about Christianity as far as religion is concerned. From Italy to England to France, this major vibrant religion had its ideas affect day-to-day lives of many. Ideally, there would not have been any form of enlightenment without Christianity. Churchmen almost had equal rights and powers as emperors and many other rulers that existed then with some privileges being exemption from paying taxes(J. Schmidt, 2007). Philosophers, thinkers and scholars like John Locke and Voltaire sparked the enlightenment. Other significant names during this period were Isaac Newton, who was a great physicist and later recognized as father of modernShow MoreRelatedThe Elements Of Gothic Fiction In Mary Shelleys Frankenstein1717 Words à |à 7 Pagesis around 1817, as this was when it was written, and was influenced by the periodââ¬â¢s movements such as ââ¬Å"The Enlightenmentâ⬠. Furthermore, the genre of the book is often described as ââ¬Å"Gothic Horrorâ⬠. This is due to the fact that, it constitutes many elements of other ââ¬Å"Gothic Fictionâ⬠texts. According to www.study.com this includes, ââ¬Å"decaying and gloomy locations, supernatural creatures and madnessâ⬠. An example of this can be found on page 58, when it states, ââ¬Å"His yellow skin scarcely covered the workRead MoreRomantic Literature : The Natural World1192 Words à |à 5 PagesLiterature focuses on the natural wor ld and the use of the human imagination to explore that world. For the Romantics, reason which was valued by the enlightenment authors found its meaning with imagination and was possibly even more important. This allowed them to ignore the strict rules in regard to diction, style and form that the enlightenments were so enthralled with. Samuel T Coleridge, one of the most popular Romantics, in his time and ours is well known to have had a substance abuse problemRead MoreAnalysis Of The Great Cat Massacre1402 Words à |à 6 Pagestext. This can best be described a tour of Dartonââ¬â¢s mind and thoughts with no particular bias. Through further analysis of Dartonââ¬â¢s The Great Cat Massacre reveals that not all subjects in the seventeenth and eighteenth century benefited from the enlightenment. These essays and short stories tell us that the peasants, described in ââ¬Å"Peasants Tell Talesâ⬠have violent, nasty, and brutal outlooks on life based on their harsh upbringi ng and the stories they told and passed down. Similarly, the workers inRead MoreEssay on Plot Overview of Hermann Hesses Siddhartha1679 Words à |à 7 Pagesallow you to reach Nirvana. Therefore, he sets out on a journey to experience the world for himself, the good and the bad, in order to become closer to enlightenment and to eventually become an enlightened one himself, a Buddha. After each experience Siddhartha comes to a new conclusion as his outlook on life changes, as he becomes closer to enlightenment. In the beginning of the book Siddhartha is already living in one extreme. He has a perfect life and is sheltered from all harm by his father, theRead MoreSiddharthas Spitiual And Intellectual Growth Essay1603 Words à |à 7 Pagesdecides to set a goal onto his life. He decides to journey along the path of enlightenment and reach Nirvana, a state of total bliss. His dear friend, Govinda, accompanies him on this journey. Siddhartha sets out to seek the path to enlightenment, but it is long and difficult. Along the way, he grows spiritually and intellectually from a young seeking Brahmin, to an old, wise, and content ferryman with the knowledge of enlightenment and possessing many insights on life. Read MoreTo Believe and To Change in Ayn Randââ¬â¢s Anthem873 Words à |à 3 PagesThe intention of totalitarian dictators enforcing the arrangement of children living apart from their families is to impede individualistic society- avert dissimilarities t ranspiring in the process of family influences in education, forfend the enlightenment of emotions, and the establishment of collectivism. ââ¬Å"We strive to be like all our brother men, for all men must be alikeâ⬠(Rand 21). Although being divergent is a sin, transgression in Anthem society, Prometheus, the protagonist, defies againstRead MoreThe Adventure Of The German Student1175 Words à |à 5 Pagesand was cold to the touch. An officer is left puzzled about the whole matter; he explained that the woman had been guillotined the day before. Wolfgang believed that a demon had possessed the dead woman in order to capture his soul. Wolfgang lost his mind and died in a mad house. I. Character: Antagonist: (prove how his secluded lifestyle led him to unmoral madness) Wolfgang is a young German student that is described by Irving as being ââ¬Å"visionary and enthusiasticâ⬠(1). Wolf gang is the protagonistRead MoreWilliam Shakespeare s As You Like It1270 Words à |à 6 Pageselements of shakespeare s, Rosalind gets banished by Duke Frederick in (i.iii.82-84), and thus disguises herself as a man (Ganymede) and escapes with Celia, her cousin, into the forest of Arden. All of this madness and chaos stands as a test to the love that Orlando and Rosalind share. Before meeting again Rosalind finds poems written on the trees of the forest in Act 3 Scene3. ââ¬Å"All the pictures fairest linââ¬â¢d, are but black to Rosalind. Let no face be kept in mind, but the fair of Rosalindâ⬠(iiiRead MoreAnalysis Of Moby Dick By Herman Melville1276 Words à |à 6 Pagesââ¬Å"There is wisdom that is woe but there is a woe that is madness.â⬠- Herman Melville. Moby-Dick is a novel that was written by Herman Melville, during the American Renaissance. Melville was an American novelist, short story writer, and a poet. Melville was influenced in his writing career by many people such as, William Shakespeare (Macbeth, Romeo and Juliet), Nathaniel Hawthorne (The Scarlett Letter, The House of Seven Gables), and Edgar Allen Poe (The Raven, The Fall of the House of Usher). He wasRead MoreAmadeus Essay 22119 Words à |à 9 Pagesbrilliant compositions. The talented but conventional and limited Salieri, on the other hand, was favored by those with the power to elevate artists to heights of fame. The film delves into this struggle of Mozarts for recognition in an allegedly Enlightenment-oriented Viennese society, and in doing so is certainly not far from accurate. Mozart and his family were needy due to absurdly low fees for his teaching, the neglectful public who did not understand or appreciate his operas, the businessmen who
Subscribe to:
Comments (Atom)