The concentration of hydrochloric Acid Essay Example for Free

The concentration of hydrochloric Acid Essay There are many factors that have an affect on the rate of a chemical reaction. The speed of reaction means how fast the reactants change into the desired product. The consequence of this is that more of the products are made in a certain period of time if it has a high rate of reaction. Factors can only have two affects on a reaction making the reaction happen faster or slower depending on how it interferes with the reaction, the factors never change the outcome of the reaction, the final product. This ability to change the rate of the reaction enables us to control reactions and predict how changing variables affects the experiment. Rate of reaction = 1 _ Time Taken Reacting chemicals must either: Collide with each other.   Collide with enough energy to break the existing bonds. The energy required to break these bonds is called the Activation Energy (EA) There are four main factors that affect reaction these are:   Temperature   Use of a catalyst Concentration   Surface area Temperature. When the temperature is increased the reactant molecules move around faster with a greater amount of energy. This means there will be more successful collisions because it is the amount of energy in the molecules that determines whether a reaction is more successful. More successful collisions resulting in reactants get used up quicker resulting in the reaction time decreasing. Catalyst A catalyst affects the reaction rate by lowering the activation energy for the reaction. This means that more collisions are successful because it is easier to reach activation energy. A catalyst does not get used up during a reaction. It can then be used again, and again. Surface area Grinding up a solid into smaller chunks creates a larger surface area by making the surface area in contact with a liquid or a solid bigger Therefore more collisions can occur which increases the number of successful reactions thus speeding up the reaction. Purpose The purpose of this investigation is to determine how one of the above factors affects a reaction. So we choose only one variable. We were given 3 reactions to choose from, each allowing us to vary a certain factor. After careful consideration we came to the conclusion that due to lack of equipment we could not test catalyst, measuring temperature would be too difficult in the classroom because we could not control the classroom temperature very well it could change over the course of the experiment, and surface area would be difficult to calculate. So we opted for the concentration variable as it was easy to measure accurately the concentration of the reactants. There were three possibilities to choose from and these were: Choice 1. Hydrochloric Acid + Sodium Thiousulphate Sodium Chloride + Water + Sulphur Dioxide. HCl (aq) + Na2 S2 O3 (aq) NACl + H2O + S + SO3 Choice 2 Hydrochloric Acid + Magnesium Hydrogen + Magnesium Chloride HCl (aq) + Mg(s) H(g) + MgCl (aq) Choice 3 Hydrochloric Acid + Calcium Carbonate Calcium Chloride + Carbon Dioxide + Water HCl (aq) + CaCO3 (s) CaCl2 (aq) + CO2 (g) + H2O (l) Preliminary tests To help me decide which one to choose I decided to do some preliminary tests the First I did the reaction between Sodium Thiousulphate and Hydrochloric Acid. This test involved putting a considerable amount of Hydrochloric Acid into a clear beaker on top of a piece of plain paper with a (X) clearly marked in the middle of the glass beaker. Sodium Thiousulphate is then dropped into the solution and the reaction forms a cloudy solution and soon the liquid becomes opaque. The timer starts from when the Sodium Thiousulphate is dropped into the solution and is stopped when the (X) under the beaker is no longer visible. How fast the reaction is depends on how quickly the mark under the beaker is no longer visible. I decided this was not a viable or easily measure test. The measuring comes down to human judgement, which varies from person to person. It would have been possible to use light sensing equipment to accurately measure the time that it takes for the cross to become no longer visible. But as this equipment was not at my disposal I decided that this test would not be accurate enough for me to get a good set of precise results. The second preliminary was the reaction between Calcium Carbonate and Hydrochloric Acid. It involved putting Hydrochloric acid into a beaker and then adding the Calcium Carbonate in the form of larger chunks, the beaker would immediately be attached to a gas syringe, this piece of equipment that measures how much gas the reaction gives off in cm3. This meant we could accurately measure how much gas is given off from the reaction, giving us a precise value rather than estimation like in the first experiment. This experiment was a better possibility because a distinct value could be recorded; human judgement was not an issue which was one of the problems with the first experiment. Unfortunately surface area is the problem with this experiment, the marble chips were difficult to measure to ensure the size of the surface area accurately. This meant that this was constantly a variable but not a variable that we could measure accurately meaning that the experiment would either have unreliable results through estimating surface area or have unreliable results through having two variable factors. The final set of preliminary tests was the reaction between Magnesium and Hydrochloric Acid. This test was set up in a very similar manner as the experiment above, as the aim in both was to measure the amount of gas given off. In this case in was Hydrogen was the gas being given off. The reaction took place in a beaker which was in turn connected to a gas syringe, measuring the Hydrogen produced. The experiment allowed us to control each of the variables. Temperature could be controlled using a water bath as with preliminary test number two. The surface area of the magnesium was much easier to control than the Calcium Carbonate of the previous experiment, this was because the magnesium was in strip form instead of unevenly sized chips. The concentration of the Hydrochloric Acid was also easy to vary, using a burette enabled us to measure the amount of water and acid being put into the beaker. Because of this ability to control all the affecting factors I felt that the Magnesium + Hydrochloric Acid was the experiment that would provide the most reliable set of results. The use of a gas syringe meant that the results collected would be both precise and accurate, with minimum human judgement involved. After choosing to do this experiment I then conducted a further set of preliminary tests. I decided to keep the experiment roughly the same although I improved the method of measuring the magnesium strips because in my original preliminary I just cut them roughly equal sizes but in this preliminary I decided that I would use a ruler to ensure equal sizes this therefore would try and eliminate the factor of surface area so that I am only testing how the concentration affects the rate of reaction by having a similar surface area. Experiment Key 1. 0 Moles 12. 50 cm3 Hydrochloric Acid 12. 50 cm3 Water 1. 1 Moles 13. 75 cm3 Hydrochloric Acid 11. 25 cm3 Water 1. 2 Moles 15. 00 cm3 Hydrochloric Acid 10. 00 cm3 Water 1. 3 Moles 16. 25 cm3 Hydrochloric Acid 8. 75 cm3 Water 1. 4 Moles 17. 50 cm3 Hydrochloric Acid 7. 50 cm3 Water Test number one Moles 10 Seconds 20 Seconds 30 Seconds 40 Seconds 50 Seconds 60 Seconds 1Test Number two. Moles 10 Seconds 20 Seconds 30 Seconds 40 Seconds 50 Seconds 60 Seconds 2 Show preview only The above preview is unformatted text This student written piece of work is one of many that can be found in our GCSE Patterns of Behaviour section.

The World Doesn’t Need Religion :: Free Argumentative Essays

The World Doesn’t Need Religion Religion has screwed us up for a long time and we'd be better off without it. By "us" I mean Americans living in the 21st century. Without religions we would have fewer labels separating us from each other and we wouldn't hate Jews or Catholics or Muslims. If we didn't have religions, we wouldn't have to convert anyone or "save" anyone. If we didn't have religions, people could no longer get caught up in the fine lines of religious rightousness or be trapped in a double-standard morality. And most importantly, we would be truly free of religious engendered guilt that never quite goes away. In America, people are less tolerant than before and words like Jew, Muslim, and Christian set us off and make us mad because we connect these labels with violence and war. We are planning to attack the "axis of evil" and in giving Iraq this label, we assume a moral duty on our part and the devil on theirs. There is no simple answer to the problems in the Middle East which are daily getting more and more out of control. But adding quasi-religious labels pushes us farther apart and increases the tension and opposition on all sides. I grew up in a Catholic family and went to Catholic grade school and high school and I don't regret it. It was an interesting experience and surely formed a great part of my character. But looking back, I see that the system of organized religion is rigged and the deck is stacked more in favor of the church than it is in favor of the faithful. Consider for a moment the Christian need to convert and save people, two more activities that could be done away with if we didn't have religion. Converting more followers keeps the organized religion afloat and promising salvation is the hook that gets people's attention. No one knows what happens after death. But some religions offer a promise of heaven or hell and, like children, we willing believe in this fantastic fairy tale. On another note, the church introduces us to the concept of guilt and tells us we are guilty even before we are born. This is the most ridiculous thing I have ever heard. Nontheless, if we find God, or Jesus, or convert, or confess before we die, we're saved.

Dubai Crisis

http://hubpages. com/hub/FINANCIAL-CRISIS-IN-DUBAI-REASINS-AND-EFFECTS FINANCIAL CRISIS IN DUBAI-REASONS AND EFFECTS Dubai-economic position That is Dubai-sky piercing towers, rotating buildings, spectacular architectural designs,flow of petro-dollers,broad and clean road notworks, etc,etc. Businessmen, investers, and lusury-seekers, used to visit Dubai with all zeal. Some weeks ago, Dubai had issued to international investers, bonds worth $1. 9trillion,whiched sent the message that its economic position is unshakable! But now that foundation has shaken! inability to rapay loan instalments All these indicate that Dubai's financial foundation is †¦Ã¢â‚¬ ¦ SHAKING! Reasons Dubai, unlike other six emirates of UAE is not a country rich with oil resources. This city state is purely a business city wholly depending upon tourism and other businesses. Dubai World, in a haste to attract world enterprenuers started spending more and more on building fine roads, star hotels,etc. Foreign institutional investers also invested much here, especially during the last four years. But, for some reason, may be due to economic crisis mainly, FIIs didnot turn to Dubai for investment.. AS a result, real-estate businessin Dubai suddenly collapsed. This made an impact on other businesses also. Effects Dubai world, has business tie-ups in different countries including India. Thes projects, may be delayed( resulting in cost increase), or dropped, or prolonged. Unemployment problem may arise in Dubai. Enterprises may have to retrench a portion of their employees.! 0 lakh Indians are working in Dubai and other UAE countries. Foreign Institutional investers, who have business ties with Dubai World, may face loss. 70 financial institutions have lent credits to Dubai world. Banks in Duabi may face crisis. When the world is recovering from last year's economic recession, this may push it back to same position. Ray of hope. Inspite of all these, experts hope that it is possible to recover. It comes out of past experience. Dubai had faced similar economic crisis in 1999. Then Abudhabhi, another emirette in UAE, had helped Dubai by lending a loan of $1,00,000. Abudhabhi is a financially stable country.. It can help. But the quantum of need this time is muchmore than it was in 1999. Just on 29th,November,Abudhabhi has announced that it would concider the financing aspect,item wise, taking each main transaction on merits. It has also clarified,it is not going to take full responsibility of all loans. †¢ Top ten financial institutions of the world By greater optimism and assurances by America, major part of the world succumbed to globalization and WTC agreements. American companies, for their profit, encouraged the buying habits of people in the globe,†¦ †¢ Finance and gold stock The economic powers in the world were amazed last week when India purchased 200 tonnes of gold from International monetary fund(IMF). This purchase needed an investment of Rs. 35,000 crores. India also announced†¦ ABU DHABI, Dec. 2 (Xinhua) — The financial crisis sweeping the world that emerged from Wall Street has taken its toll on the United Arab Emirates (UAE), sending the Gulf oil producing country's economy into an uncertain path. In the first half of 2008, the world saw a steady rise in oil prices, which climbed to a record high of 147. 27 U. S. dollars a barrel on July 11. However, the soaring oil prices did not get a firm footing since then, with the supply and demand factors remained in a balance, as top officials of the oil cartel Organization of Petroleum Exporting Countries (OPEC) had said repeatedly. After the speculative factors gave way to the fundamentals in the market, oil prices began a journey of correction, declining below 60 dollars a barrel, which represented a drop of more than 60 percent compared with the peak in July. The decline of oil prices was no good news for the UAE, for the oil sector accounted for about 35. 9 percent of the country's GDP in 2007. Local newspaper Gulf News estimated in July that the oil revenue of Abu Dhabi whose production accounts for nearly 94 percent of the UAE's crude oil output, would reach 100 billion dollars if the price remained on high level. But the figure seems impossible now. In addition to oil prices, the UAE is facing a reverse in its property market which has been booming since the government allowed foreign investors to buy property on a freehold basis in 2002. A report released by Morgan Stanley in August predicted a decline of 10 percent by 2010 in the property market of Dubai, the UAE's commercial and financial hub. But the correction of prices in the UAE's property market came earlier than Morgan Stanley predicted. In November, HSBC said in are port that property prices fell in October by four percent in Dubai and five percent in Abu Dhabi, which is the first ever since2002 and may be a turning point of the six-year bull market. In the stock markets, the UAE has been suffering a free fall this year, a similar experience that some emerging markets had during the same period. On Nov. 16, the Dubai Financial Market (DFM) index closed at 1,981. 4 points, falling by 68. 51 percent from the year's peak of 6,291. 87 points on Jan. 15 with a loss of 4. 67 billion dirhams (1. 27billion dollars) in market value. On the same day, the Abu Dhabi Securities Exchange (ADX) also fell to its lowest point this year, with its general index hitting2,755. 62, down 46. 48 percent from 5,148. 49 points on June 11 with a loss of 1. 52 billion dirhams. BANKS' TIGHTENING PURSE STRINGS The UAE Central Bank held a meeting with representatives from all banks operating in the country on Sept. 8, three days after the U. S. investment bank Lehman Brothers filed for bankruptcy, to assess the status of the UAE banking system. A statement released by the Central Bank after the meeting said that the UAE banks had no exposure to Lehman Brothers and there was no systemic risk in the UAE. But the statement also revealed that the country's banking system was also facing a lack of liquidity by saying that â€Å"various suggestions for boosting liquidity of banks were also discussed. † On Sept. 2, the Central Bank announced the establishment of an emergency lending facility worth 50 billion dirhams for banks operating in the country, marking the first move to inject liquidity since the Wall Street meltdown emerged. After that, the UAE government took more steps to shore up the banking system. The Central Bank announced on Oct. 8 a two-percentage-point cut in its lending rate to 3 percent in a bid to boost liquidity of local banks. It also lowered the rate on its repurchase of certificate of deposit (REPO) from 2 percent to 1. percent with effect from Oct. 8. In mid-October, the UAE cabinet said that it decided to take preventive measures to support the banking system. Under the measures, the government will provide a three-year guarantee to deposits and savings in all national banks and foreign banks with â€Å"significant operations† in the country. In addition, the government will also guarantee all inter-bank lending operations between banks operating in the country and inject sufficient liquidity in the financial system if and when necessary. The government also decided to inject another 70 billion dirhams into the banking system. Despite the measures taken by the government, the lack of liquidity has made banks operating in the UAE tighten their purse strings. HSBC raised its minimum salary requirement for a personal loan from 5,000 dirhams to 10,000 dirhams in October and doubled it again in November to 20,000 dirhams. Another major foreign bank operating in the UAE Lloyds TSB decided in November to stop lending to customers who wanted to buy apartments. In the meantime, the bank lowered its loan to value ratio on villas to 50 percent from 80 percent in October. The UAE's national banks, including the country's largest bank Emirates NBD, were also reportedly tightening their credit. UNCERTAIN PROSPECT OF MEGA PROJECTS In the past few years, the UAE has witnessed a boom in its property market, with prices quadrupled. The property sector became an important contributor to the country's efforts to diversify its economy so as to reduce the dependence on the oil industry. Property developers in the UAE launched a series of iconic projects during the boom, including the three Palm Islands and Burj Dubai, the highest architecture to date in the world. The success of those iconic projects in promoting themselves and their developers and the continuous upturn in the property market have encouraged developers float more mega projects. In October, Nakheel, the developer of the Palm Islands, announced a new project named â€Å"Nakheel Harbor & Tower. † The project, which will cover an area of more than 270 hectares and accommodate over 55,000 people, will include a tower more than 1,000 meters high. If completed, the Nakheel Tower will take Burj Dubai's title of the world's highest building, whose current height stands at 688 meters. According to Nakheel, the Nakheel Harbor & Tower will take more than 10 years to complete. Now, with the credit squeeze and a possible bear market for the property sector, the project's fate seems uncertain. In fact, Nakheel said in mid-November that it will reassess its â€Å"immediate business objectives to accommodate the current economic climate. †¦ The next few months will see a scaling back of activity around some of our projects. â€Å"

Useful Phrases to Learn for French Class

If you are a student of French, you should learn typical classroom requests and statements expressed as French words and phrases. The more you use French in context and hear it spoken, the more you will internalize it. After a while, it becomes natural, as though youve always known it. The younger you are, the easier it is to learn another language; the older you get, the more you need to practice. Essential Phrases to Use in  French Class Pay close attention to how you say these words and phrases in French, particularly the vowels, which require you to open your mouth and elongate your lips  much more than in English. If you say a French  o,  for instance, form your lips in the shape of an o; youd be surprised how much this helps achieve a true French sound. Click on the links to hear how the words and phrases are pronounced. To make it easier to learn how to say the word or phrase in French, the meaning is given first in English, followed by the French translation: What?   Comment?I dont know.   Je ne sais pas.I dont understand.   Je ne comprends pas.I have a problem.   Jai un problà ¨me.I have a question.   Jai une question.What page?   Quelle page?I forgot my ___.   Jai oublià © mon/ma ___. May I borrow a ___?   Puis-je emprunter un/une ___ ?May I go to the bathroom?   Puis-je aller aux toilettes?I would like (to) ___.   Je voudrais ___.I need (to) ___.   Jai besoin de ___. Essential  Words to Use in  French  Class Sometimes you only need a single word to make your point clear in class. The examples show you how to say classroom words in French: Yes  Ã‚  ouiNo  Ã‚  non  OK  Ã‚  daccord  Who  Ã‚  quiWhat  Ã‚  quoi  When  Ã‚  quand  Where  Ã‚  oà ¹Why  Ã‚  pourquoiHow  Ã‚  comment Translating Asking how to say words in French class will be easier with the following translations: How do you say ___ in French?   Comment dit-on ___ en franà §ais?What is ___ in French?  Ã‚  ___, cest quoi en franà §ais?What does ___ mean?   Que veut dire ___ ?What is the English translation of this sentence?   Quelle est la traduction de cette phrase? Listening and Understanding Youll know how to ask for help in the classroom after you study the following questions and requests: Repeat,  please.   Rà ©pà ©tez, sil vous plaà ®t.One more time   Encore une foisSlower (Or: More slowly)   Plus lentementHow do you spell it?   Comment est-ce que cela sà ©crit?Can you write it?   Pouvez-vous là ©crire?Whats the difference between ___ and ___?   Quelle est la diffà ©rence entre ___ et ___ ?Is this sentence correct?   Cette phrase est correcte? Resources and Tips In addition to classroom words and phrases, take the time to review  essential French,  greetings, terms of politeness, and additional words for  school and supplies, as well as the most common  French phrases  and  words. If you need more practice to feel comfortable using these expressions, try enlisting a friend or family member to help you: For instance, one of you could say the expression in English, while the other gives the translation in French.