Introduction to Buffer Solutions

Introduction to Buffer Solutions Introduction Buffer solution is a solution consisting a mixture of weak acid and its conjugate base . Furthermore they declare that buffer solutions are very essential to keep the pH value nearly constant in variety of chemical application. ( Crowe and Bradshaw 2010) Many life forms thrives only in a relatively small pH range so they utilize a buffer solution to maintain a constant pH, one common example of a buffer solution found in nature is blood. buffer solution is very vital t keep the pH at a constant value in variety of enzymes in many organisms to work this is due to different enzymes work at different prà ©cised pH. On the same way they state that if the pH range moves above or below the range, the enzymatic action either stops or can denature where there are many cases denaturation can permanently disable their catalytic activity. ( Kotz, Treichel and Townsend ,2009) Buffer of carbonic acid and bicarbonate is present in blood plasma maintain pH between 7.35 to 7.45.Over more they clarify that there are two main types of buffer system, Acid buffer system: the solution containing large amount of weak acid and its salt with strong base is termed as acidic buffer solution. pH = pKa + log [salt] / [acid] Basic buffer system: the solution containing large amount of weak base and its salt with strong acid is termed as basic buffer solution. pOH = pKb + log [salt] / [base] (Moore, Stanitski and Jurs (2009) In living organisms including human the important buffer solution to maintain the ph of the blood is bicarbonate buffering system. On the other hand they state that this bicarbonate buffer system tends to maintain relatively constant plasma pH, where carbon dioxide combines with water to form carbonic acids which in turn rapidly dissociate to form hydrogen ions and bicarbonate ions.( Lanham et al ,2011) CO2 + H2O H2CO3 HCO3 + H+ Blood is dumped by excess hydrogen ions, some of those hydrogen ions associate with bicarbonate forming carbonic acid results in increase in acidity of the blood. As well as they elaborate that due to this incident the buffering system becomes powerful regulator of acidity by accompanying with respiratory compensation in which breathing is altered to modify the carbon dioxide in circulation which results in increase in ventilation therefore increase the loss of carbon dioxide into the atmosphere. (Rhoades and Bell (2012), pH meter is a electronic device that is used to measure the ph of the solution, where a typical pH meter consists of a special measuring probe connected to an electronic meter that measures and display the reading. (Kenkel,2013) Objectives To know how to prepare buffer solution. To practice again how to prepare standard solution. To know how to measure the pH using pH meter. Materials Used Electronic balance Pipette Measuring cylinder Watch glass Beaker pH meter Volumetric flask (100ml) NaHPO4 powder (0.7 g) Na2HPO4 powder (1.56 g) Sodium hydroxide pellets Ammonium chloride powder Glass rod Spatula Methodology At pH 7 NAHPO4, 0.70g and Na2HPO4, 1.56g was taken and measured using the electronic balance. Then both NAHPO4 and Na2HPO4 were mixed together into the volumetric flask. First half of the volumetric flask was filled with distilled water and dissolved by inverting. Later on the flask was filled with distilled water till it reaches the meniscus level. Finally the pH was measured. At pH 10 NH4OH NH4+ + OH; pKb = 4.74 pOH = pKb + log [NH4+] / [NH3] pKw = pH + pOH 14 = 10 + pOH pOH = 4 pOH = pKb + log [NH4+] / [NH3] 4 = 4.74 + log [NH4+] / [NH3] [NH4+] / [NH3] = 10 -0.74 = 0.181 NH4CL, 0.1m standard solution was made. Afterwards NaOH, 0.34g was measured using the electronic balance. NaOH of 0.34g was obtained by, NH4+ + OH- NH3 + H2O x 0.1 – x 0 x [NH4+] / [NH3] = 0.181 X = 0.085M of OH- Number of mole of NaOH = 0.085 x (100 / 1000) = 0.0085 mols Mass of NaOH = 0.0085 x 40 = 0.34g Then afterwards 0.34g of NaOH was dissolved in 0.1 M of NH4Cl to form a buffer solution. NaOH, 0.1m standard solution was made. Afterwards NaOH, 0.34g was measured using the electronic balance. NH4Cl of 0.63g was obtained by, NH4+ + OH- NH3 + H2O x 0.1 x – 0.1 0 0.1 [NH4+] / [NH3] = 0.181 X = 0.1181M of NH4+ Number of mole of NH4Cl = 0.1181x (100 / 1000) = 0.01181 mols Mass of NH4Cl = 0.01181 x 35 = 0.63g Then afterwards 0.63g of NH4Cl was dissolved in 0.1 M of NaOH to form a buffer solution. Later on using the pH meter the final ph of each buffer solution was measured approximately. Results Discussion / Conclusion Every precise work the pH meter should be calibrated before each measurement, at every experiment the calibration is done because the glass rode does not give reproducible electro motive force over longer periods of time. Additionally further he states that pH meter calibration should be performed with at least two standard buffer solutions that span the range of pH values to be measured. (Hauser 2001) Single measurement the probe should be rinsed with distilled water to remove any traces of solution being measured and then it should be blotted using the scientific wipe to absorb any remaining water which could dilute the sample which alters the reading. (Prichard 2003) Reference Crowe, J and Bradshaw, T (2010). Chemistry of biosciences: the essential concepts. Google Books [Online].Availableat:http://books.google.lk/books?id=onacAQAAQBAJpg=PA578dq=buffer+solutionhl=ensa=Xei=UkOuU7OtJJO78gXkvIDYDQredir_esc=y#v=onepageq=buffer%20solutionf=false(Accessed: 28 Aug 2014) Kotz, J., Treichel, P and Townsend, J (2009). Chemistry and chemistry reactivity, enhanced edition. Google Books [Online]. Available at: http://books.google.lk/books?id=IBESYmQcb0sCpg=PA851dq=buffer+solutionhl=ensa=Xei=u0CuU4PYBYS78gXVpoGIAwredir_esc=y#v=onepageq=buffer%20solutionf=false (Accessed: 28 aug 2014) Moore, J., Stanitski, C and Jurs, P (2009). Principles of chemistry: the molecular science. Googke Books [Online]. Available at: http://books.google.lk/books?id=ZOm8L9oCwLMCpg=PA575dq=buffer+solutionhl=ensa=Xei=u0CuU4PYBYS78gXVpoGIAwredir_esc=y#v=onepageq=buffer%20solutionf=false (Accessed: 27 aug 2014) Lanham, S.A., Stear,S., Shirreffs,S and Colins, A (2011). Sports and exercise nutrition. Google Books [online]. Available at: http://books.google.lk/books?id=YePJM98Np5MCpg=RA1PT115dq=blood+acting+as+bufferhl=ensa=Xei=E0KuU8ypKYb_8QWLh4G4Awredir_esc=y#v=onepageq=blood%20acting%20as%20bufferf=false (Accessed: 28 aug 2014) Rhoades, R.A and Bell, D.R (2012). Medical physiology: principles of clinical medicine. Google Books [Online]. Available at: http://books.google.lk/books?id=1kGcFOKCUzkCpg=PA457dq=blood+acting+as+bufferhl=ensa=Xei=E0KuU8ypKYb_8QWLh4G4Awredir_esc=y#v=onepageq=blood%20acting%20as%20bufferf=false (Accessed: 28 June 2014) Kenkel, J (2013). Analytical chemistry for technicians fourth edition. Google books [Online]. Available at: http://books.google.lk/books?id=JZAAAAAAQBAJpg=PA400dq=ph+meterhl=ensa=Xei=0LOuU8T0Os7r8AWY0oHwAgredir_esc=y#v=onepageq=ph%20meterf=false (Accessed: 27aug 2014) Hauser, B (2001). Drinking water chemistry: laboratory manual. Google Books [Online]. Available at: http://books.google.lk/books?id=SVxcRu68YGwCpg=PA28dq=calibration+of+ph+meterhl=ensa=Xei=lQ2wU_GhI8yB8gWx9oDAAwredir_esc=y#v=onepageq=calibration%20of%20ph%20meterf=false (Accessed: 26 aug 2014) Prichard, E (2003). Measurement of pH. Google books [Online]. Available at: http://books.google.lk/books?id=HNJy5rtJLjACpg=PA2dq=ph+meterhl=ensa=Xei=0LOuU8T0Os7r8AWY0oHwAgredir_esc=y#v=onepageq=ph%20meterf=false (Accessed: 28 aug 2014)

School Crime And Violence

Crime and violence in schools are issues that are of significant public concern, especially after the series of tragic school shootings recently. The schools have exercised care in making the students safe but many schools are now facing serious problems so that effective strategies can be devised to prevent school violence and increase school safety. (Small and Tetrick). The terms â€Å"school violence† and â€Å"school safety,† are still terms that need to be commonly defined. The authors maintain that â€Å"Multiple approaches can prove beneficial as each discipline brings to bear the full force of its knowledge and experience, but they complicate the task of summarizing the state of school violence. For instance, should school violence be considered a subset of youth violence? †(Small and Tetrick). Most of the violence in schools are involved in gangs. A gang is a group of people who form an allegiance for a common purpose and engage in unlawful or criminal activity. Gangs give members companionship, guidance, excitement and identity. When a member needs something, the others come to the rescue and provide protection. Gangs members have significantly lower levels of self-esteem compared to their non-gang peers. They also could name fewer adult role models than did their non-gang ,peers. It is no doubt that America has become a violent society. Television programs alone show gruesome murders and violence as if they are normal incidences in our lives. It is said that children learn to imitate the violence that they see on television. These take root in a lot of issues, foremost of which is on gun control. The positive effects of the strict enforcement of gun laws are readily seen. The Brady Campaign, for example believes that â€Å"background checks nationwide stopped over 600,000 felons and other prohibited purchasers from buying handguns from federally licensed firearm dealers. † Some say this is one big reason why there is a need to advocate gun control. Once people realize that there is a direct correlation between the increases in violence as correlated with gun possession, they would also be against gun violence in society. However, opinions are at odds with regards to the issue of gun control. Remarkably, both advocates and opponents of gun control policies in the United States use statistics to back up their stance. The Bureau of Justice Statistics reports that: According to the National Crime Victimization Survey (NCVS), in 2003, 449,150 victims of violent crimes stated that they faced an offender with a firearm. Incidents involving a firearm represented 7% of the 4. 9 million violent crimes of rape and sexual assault, robbery, and aggravated and simple assault. The FBI's Crime in the United States estimated that 67% of the 16,503 murders in 2003 were committed with firearms. â€Å"Gun Control vs. Gun Rights). Advocates of gun control directly use statistics such as this to assert that the increase in violence is positively correlated with gun possession. Organizations such as the National Rifle Association of America (NRA) and other proponents of gun rights oppose such view. Alexander, for one, insists that such arguments contradict factual studies. He contradicts the correlation, saying that â€Å"cities with the most restrictive gun laws, like Washington, D. C. , and Atlanta, Georgia, in fact, have the highest murder rates in the nation. At the center of the gun control issue is the Second Amendment to the Constitution: â€Å"A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms shall not be infringed. † Arguments usually focus on the interpretation of the law. The Second Amendment is the main banner of gun rights activists. Gun control advocates, on the other hand, feel that gun control opponents misinterpret the law when they assume that it means absolute right to ownership of guns by private individuals (Krouse). They assert that the Second Amendment only refers to gun ownership in situation of â€Å"militia† and not for general purposes. Gun control supporters feel that gun possession by just anybody is a contributing cause of increased incidence of crimes in the United States. In Guns and Terror, Berger and Henigan present studies to support their statement that â€Å"Gun shows are a breeding ground for gun sales to terrorist [and that] nothing in federal law prevents terrorists from quickly amassing arsenals of weapons† (4). Opponents to the gun control movement also believe that there is not enough factual evidence to the other side’s claim that banning the sale of some kinds of guns result to lower crime rates (â€Å"Gun Control vs. Gun Rights†). Alexander accuses gun control groups of ‘demagogue-ing’ the issue and maintains that the root of the problem is culture, and not the gun. He even notes that â€Å"many of the problems in question are the result of Leftist doctrines. † The Brady Campaign believes that stricter rules on gun ownership will result in communities with minimal crimes since they correlate guns with most crimes committed. Proponents of gun control also base this belief on what they see as positive effects of enforcement of gun laws. The Brady Campaign, for example believes that â€Å"background checks nationwide stopped over 600,000 felons and other prohibited purchasers from buying handguns from federally licensed firearm dealers. † Gun rights proponents maintain that stricter rules could actually cause crime rates to rise as criminals only tend to go places with stricter gun rules. Alexander quotes Thomas Sowell as saying, â€Å"Most criminals aren’t that stupid; they tend to go where the guns aren’t. †(Brady Campaign to Prevent Gun Violence). Proponents of gun control continue to push for the passage of new laws and/or amendments to existing laws to restrict gun ownership. For one, they are lobbying for legislation covering what they refer to as loopholes, specifically in issues such as juvenile access to firearms, and sales at gun shows and through the Internet (Brady Campaign). Opponents are also continuing efforts to gather support to counter the move of gun control advocates. The NRA is drawing support through massive information drive advocating Second Amendment rights and the protection of Americans’ hunting heritage. The NRA also performs studies and surveys contradicting the position of gun control supporters. In their survey on what Americans think of Right-to-Carry laws, results show that 79% of the voters stood in favor of such laws (National Rifle Association of America). The Brady Campaign notes, â€Å"according to an analysis of the FBI Uniform Crime Report, the percentage of violent crimes committed with firearms has declined dramatically after the Brady Law went into effect. † Supporters of gun control assert the need for more restrictions in gun ownership, especially in the federal level. They call for stricter background checks for people who intend to purchase licensed firearms. Gun rights supporters do not see additional laws and amendments to laws as a solution to increase in crime rates. Alexander writes, â€Å"Gun restrictions have not protected citizens in Atlanta, Washington, D. C. , New York or Boston, much less anyone in Columbine or Red Lake. Nor did such laws protect Jews from Hitler or Stalin or Chinese peasants from Mao, etc. , ad infinitum. † Alexander also advises politicians and gun controllers alike to look at the cultural aspects of the problem and not the instruments. The National Rifle Association of America has opposed every effort by gun control advocates, specially the Brady Campaign group, which they think will encroach on their rights under the Second Amendment. They maintain that gun ownership is their constitutional right and should not be limited to recreational purposes only. The NRA, in fact, is supporting enactment of laws involving Self-Defense and â€Å"freedom† to carry guns (Alexander, Mark 2005). Indeed, the right of law-abiding citizens to carry concealed firearms for purpose of self-defense has become a hot and controversial topic and one that will continue to be so for a long time. Schools need to protect the children from these gun-toting individuals and avoid another Columbine or Virginia Tech incident.

Common Prepositions for ELS/EFL Students

The following list contains the key English prepositions for English language learners. There are more than 150 English prepositions in English. However, this list contains the most commonly used and serves as an excellent starting English prepositions list for most learners and classes. These English prepositions are divided into one word, two-word prepositions and three-word prepositions. The two word and three words English prepositions are also known as prepositional phrases. One Word Prepositions aboutaboveacrossafteragainstalongamongaroundasatbeforebehindbelowbeneathbesidebetweenbeyondbydespitedownduringexceptforfrominincludinginsideintolikenearnextofoffonontooppositeoutoutsideoverpastthroughtotowardtowardsunderuntilupuponwithwithout Two Word Prepositions according toahead ofaside frombecause ofclose todue toexcept forfar frominside ofinstead ofnear tonext toout fromout ofoutside ofregardless of Three Word Prepositions as far asas well asby means ofin accordance within addition toin case ofin front ofin place ofin spite ofon account ofon behalf ofon top ofwith regard to

Essay Entrepreneurship - Starting Your Own Business

Entrepreneurship defined by Jeff Cornwall at Belmont University is, â€Å"A process of identifying, evaluating, seizing an opportunity and bringing together the resources necessary for success.† (www.belmont.edu) There are a wide variety of risks when it comes to starting and running your own business, just some of them are: under capitalization, poor management, market misjudgment, and lack of planning. Lack of planning and under capitalization go hand-in-hand because if you don’t properly plan your strategies and what you would like to do in the future of the company you are trying to start, then you aren’t going to be able to afford it. Like when someone says â€Å"Just looking!† while searching for a car, you put yourself in a weaker position†¦show more content†¦Working under this kind of prejudice might rule some people out of choosing an entrepreneurial life style, however, there are some people who find working under such conditions fun be cause they can try to prove how not everyone follows those shady tactics. â€Å"Tenacity, street smarts, the ability to pivot, resiliency, inspiration, and the willingness to accept risk†¦Ã¢â‚¬  (www.actionmba.org, 2010) Are personality traits you should have to be successful in the world of entrepreneurship. There will most likely be times during your endeavor that people will give up on you, your idea, or both and you should have the drive to back up your goals no matter what. You should be able to pivot according to where the market goes and have the ability to be successful and innovative in a wide spectrum of situations. On the flip side, some people believe that you don’t necessarily need to be born with such traits to become a great business owner; all it takes is some practice to love and nurture these traits so that they become just like habit! Or maybe all you need is one of these traits that can be linked to others so that you can pick them up quickly†¦ Further studying needs to happen before we can know for sure but for now we do know that if you are strong and motivated, then little will be able to stop youShow MoreRelatedEntrepreneurship Should Be Aware At The World Of Entrepreneurship Essay1531 Words   |  7 PagesALTHOUGH OWNING A BUSINESS HAS MANY BENEFITS AND PROVIDED MANY OPPORTUNITIES ANYONE PLANNING TO ENTER THE WORLD OF ENTREPRENEURSHIP SHOULD BE AWARE OF ITS POTENTIAL DRAWBACKS Introduction:- Entrepreneurship is defined as the practice of beginning a new trade or reviving an existing business, for capitalizing on fresh opportunities. The statement were analyzing today is all about entrepreneurship. The author here is trying to explain that like every coin has two sides, entrepreneurship also has benefitsRead MoreBusiness School At Washington University Essay944 Words   |  4 PagesDescribe your interest in entrepreneurship. Please include any past experiences in innovation and entrepreneurship: Ever since I was a young child I always wanted to create the next newest and biggest invention. For example, when I found out the creator of Jibits for crocs (those small plastic accessories that go into the holes of crocs sold her company to crocs for millions of dollars. It was such a simple idea, but also so creative and innovative. I was hooked on the idea of creating a productRead MoreMy Interest in Studying Entrepreneurship835 Words   |  4 Pagesfollow was entrepreneurship. Entrepreneurship is increasing in popularity as many more countries and organizations are trying to get their youth engaged at an early age with entrepreneurship with the express purpose of ensuring that innovation and entrepreneurship will thrive in the future (Mark). I want to become a successful entrepreneur because it has always been a dream of mine to become self-employed. I believe I have the leadership, passion, courage, vision, and persistence to start my own businessRead MoreThe Importance of Ent repreneurship Essay1180 Words   |  5 PagesEntrepreneurship Term Paper â€Å"Entrepreneur is defined as a person who starts a business and is willing to risk loss in order to make money.† (Merriam-Webster.com) Since before the Great Recession, economists have recognized how important entrepreneurship is to the health of the U.S. economy. (Strangler) â€Å"There are four benefits to the U.S. from entrepreneurs risk-filled but successful efforts. Entrepreneurs (1) use innovations to improve the quality of life, (2) create new jobs, (3) improveRead MorePersonal Statement : My Own Company1257 Words   |  6 Pagessophomore at Villanova University in the business school, I am still trying to figure out the path I want to take in terms of my career. Currently I am in the marketing department, but one thing I am interested in is entrepreneurship. The idea of starting my own company is very intriguing to me, and that is why I choose to speak to Tom Greenwood. Mr. Greenwood is my mother’s friend, he was previously invested in real estate before he decided to open his own business, a winery and bistro in my home townRead MoreEntrepreneurship Is A Vital Element For Invigorating Monetary Development And Employment Opportunities1361 Words   |  6 Pageshappened in the last decade has made entrepreneurship and even innovation that become an integral part of its, important in countries. When the states began to transfer production to the private sector in the market conditions, private sector tended to be more entrepreneurial. When the increase of knowledge production, distribution and use supported this, entrepreneurship began to come to the fore. The meaning of entrepreneurship, starting one’s own business was established by Richard Cantillon inRead MoreDesigning A One Stop Shop For Aspiring Entrepreneurs918 Words   |  4 Pagesone-stop shop for aspiring entrepreneurs who need assistance into building their business form the ground up. This application main task is to assist users in the steps of getting their business off the ground giving them access to tips, tools, and resources that will allow them to successfully start a business. The application will be called â€Å"The Startup† since it’s assisting users in starting up their own business. The target users for this application are for particularly for college studentsRead MoreEntrepreneurship, Franchising and Small Business.1460 Words   |  6 PagesIntroduction to Business Assignment #01: On Chapter #3 #4 Chapter #3: Entrepreneurship, Franchising and Small Business. 09. Why would a person want to own a franchise of a major well-known franchisor? 10. What is an intrapreneur? Why do some firms encourage intrapreneurship? Chapter #4: Social Responsibility and Business Ethics. 09. Why is insider trading illegal? Chapter#3: Entrepreneurship, Franchising and Small Business Question #09: Why would a person want to own a franchiseRead MoreThe Teachability Dilemma of Entrepreneurship1296 Words   |  6 Pagesrisk for the sake of a business, but also they provide our economy with employment opportunities and culture. A society can only be prosperous only when it rewards and encourages entrepreneurial activity because in fact, it is the entrepreneurs and their activities that are the critical factor for success, prosperity, growth and opportunity in any given economy. Entrepreneurship is not easy and it comes with its own risks and up and downs. On the last decade, entrepreneurship has rose and expandedRead MoreEssay On Should You Get An Mba Before Launching Your Startup1202 Words   |  5 PagesYou Get an MBA Before Launching Your Startup? The Value of an MBA or Business Education in Today’s Competitive Arena for Entrepreneurship Engineers, self-made entrepreneurs and bootstrap enthusiasts believe that the right person with the right work ethic can succeed in business with a good idea activated at the right time. However, in todays complex, collaborative and highly technical business environment, a degree in business--or at least some strong business courses--can give you the knowledge