Beers Law Definition and Equation

Beer's Law Definition and Equation Beers Law is an equation that relates the attenuation of light to properties of a material. The law states the concentration of a chemical is directly proportional to the absorbance of a solution. The relation may be used to determine the concentration of a chemical species in a solution using a colorimeter or spectrophotometer. The relation is most often used in UV-visible absorption spectroscopy. Note that Beers Law is not valid at high solution concentrations. Other Names for Beers Law Beers Law is also known as the Beer-Lambert Law, the Lambert-Beer Law, and the  Beer–Lambert–Bouguer law. The reason there are so many names is because more than one law is involved. Basically, Pierre Bouger discovered the law in 1729 and published it in Essai doptique sur la gradation de la lumià ¨re. Lambert quoted Bougers discovery in his Photometria in 1760, saying absorbance of a sample is directly proportional to the path length of light. Even though Lambert didnt claim discovery, he was often credited with it. August Beer discovered a related law in 1852. Beers law stated the absorbance is proportional to the concentration of the sample. Technically, Beers law relates to only to concentration, while the Beer-Lambert law relates absorbance to both concentration and sample thickness. Key Takeaways: Beer's Law Beers law states that the concentration of a chemical solution is directly proportional to its absorption of light.The premise is that a beam of light becomes weaker as it passes through a chemical solution. The attenuation of light occurs either as a result of distance through solution or increasing concentration.Beers law goes by many names, including the Beer-Lambert law, Lambert-Beer law, and Beer-Lambert-Bouguer law. Equation for Beers Law Beers Law may be written simply as: A ÃŽ µbc where  A is absorbance (no units)ÃŽ µ is the molar absorptivity with units of L mol-1  cm-1 (formerly called the extinction coefficient)b is the path length of the sample, usually expressed in cmc is the concentration of the compound in solution, expressed in mol L-1 Calculating the absorbance of a sample using the equation depends on two assumptions: The absorbance is directly proportional to the path length of the sample (the width of the cuvette).The absorbance is directly proportional to the concentration of the sample. In this example of the Beer-Lambert law, a green laser is attenuated as it passes through a solution of Rhodamine 6G. Amirber How to Use Beers Law While many modern instruments perform Beers law calculations by simply comparing a blank cuvette with a sample, its easy to prepare a graph using standard solutions to determine the concentration of a specimen. The graphing method assumes a straight-line relationship between absorbance and concentration, which is valid for dilute solutions.   Beers Law Example Calculation A sample is known to have a maximum absorbance value of 275 nm. Its molar absorptivity is 8400 M-1cm-1. The width of the cuvette is 1 cm. A spectrophotometer finds A 0.70. What is the concentration of the sample? To solve the problem, use Beers law: A ÃŽ µbc 0.70 (8400 M-1cm-1)(1 cm)(c) Divide both sides of the equation by [(8400 M-1 cm-1)(1 cm)] c 8.33 x 10-5 mol/L Importance of Beers Law Beers law is especially important in the fields of chemistry, physics, and meteorology. Beers law is used in chemistry to measure the concentration of chemical solutions, to analyze oxidation, and to measure polymer degradation. The law also describes the attenuation of radiation through the Earths atmosphere. While normally applied to light, the law also helps scientists understand the attenuation of particle beams, such as neutrons. In theoretical physics, the Beer-Lambert law is a solution to the Bhatnagar-Gross-Krook (BKG) operator, which is used in the Boltzmann equation for computational fluid dynamics. Sources Beer, August (1852). Bestimmung der Absorption des rothen Lichts in farbigen Flà ¼ssigkeiten (Determination of the absorption of red light in colored liquids). Annalen der Physik und Chemie. 86: 78–88.Bouguer, Pierre (1729). Essai doptique sur la gradation de la lumià ¨re. Paris, France: Claude Jombert. pp. 16–22.Ingle, J. D. J.; Crouch, S. R. (1988). Spectrochemical Analysis. New Jersey: Prentice Hall.Lambert, J. H. (1760). Photometria sive de mensura et gradibus luminis, colorum et umbrae [Photometry, or, On the measure and gradations of light, colors, and shade]. Augsburg (Augusta Vindelicorum), Germany: Eberhardt Klett.Mayerhà ¶fer, Thomas Gà ¼nter; Popp, Jà ¼rgen (2018). Beers law - why absorbance depends (almost) linearly on concentration. Chemphyschem. doi:10.1002/cphc.201801073

Fight the Power essays

Fight the Power essays Public Enemy wrote a song about racism, censorship and freedom. This song was popular among its time back in the late 80s and earlier 90s. The song Im talking about of course is Fight The Power, the title its self is self explanatory. Public Enemy has four members all from unique backgrounds. Its first and most known member would be Chuck D also known as Carlton Ridenhour born on August 1st 1960 same as its second member Professor Griff a.k.a Richard Griffin. Third member of P.E. is Terminator X born as Norman Rogers in 1966 and its fourth and final member is Flavor Flav also known to his family as William Drayton born on March 16th 1959. Public Enemy got their name from So Hank Schocklee when he heard two songs from them featuring the words Public Enemy and a single titled the same. The group toured with such groups as U2, Anthrax and Primus, and Sister of Mercy. Their first tour was the Ill tour headlining the Beastie Boys. Public Enemy is a political group. Theyve always talked about the issues at hand. And they werent afraid to use it in their songs. Their one of the few groups at their time to rap about the issues. Cause at their time gangsta rap had started to take off and people started to listen to different things. But the song Fight The Power was a popular song and so was its music video. The video showed a community coming together at a rally to support a common cause. Also in the video people who looked like they were part of the Black Panthers. The song talks about censorship briefly and I quote While the Black bands sweatin Our freedom of speech is freedom or death We got to fight the powers that be. Not only are they talking about freedom of speech but also racism comes up as part of it. They talk about how blac ...

Human beings' activity with global warming Essay

Human beings' activity with global warming - Essay Example The most notable of all greenhouse gases is carbon dioxide, which has the capability to continue being in the atmosphere for a lengthy time span. It is a scientifically proven fact that this gas could bring about a noteworthy rise in the temperature. At this point, it is but obvious to raise the question â€Å"No doubt, carbon dioxide is a very potent gas; but how are human beings responsible for rise in the levels of this gas?† The subsequent paragraph would be attempting to answer this. (1) Human beings, purely for furthering their own interests, have brought about a drastic rise in the levels at which fossil fuels are combusted. This has been for the purposes of generating electricity, heating, transportation and cement manufacturing, among many others. It is being estimated that, on account of all these activities, the annual carbon dioxide emissions are approximately 22 billion tons, on a global basis. Almost as a direct result of that, the atmospheric concentration of ca rbon dioxide has risen by roughly thirty percent. As a matter of fact, these facts are more than sufficient to convince even the most skeptical that it is nothing other than human activity predominantly responsible for heightened global warming. (1) Scientists have estimated that during the course of the last century, there has been a rise in temperature of surface of Earth to the extent of one degree Fahrenheit. The fact has been highlighted that in this very duration there is also a 25 percent increase in the carbon dioxide concentration in the atmosphere. It has been mentioned earlier in the write-up that the enhanced levels of carbon dioxide are chiefly attributable to various human activities. Extensive studies aimed at understanding the link between the above rise in temperature and increase in carbon dioxide concentration came out with a key observation: human activity is mainly responsible for the scenario where the Planet has become warmer. (2) Simultaneously, the scientist s also suggested that even some natural parameters could have played a role in global warming. In fact, with regard to the pattern of global warming, the scientists have divided the previous century into two halves. They state that, when the warming of the first half is taken into account, the natural factors must have been primarily responsible for the advent of the phenomenon. This is because; in that particular phase, various human activities resulting in carbon dioxide emissions were on the lower side. But when the second half of the century (1900-2000) is considered, it is but obvious that human beings are the chief contributors to the rise in global warming. In this period, the diverse commercial pursuits of people have led to an alarming rise in the levels of carbon dioxide emissions, and this is a fact beyond any dispute. So, it can safely be inferred that the natural parameters did not have a major role in global warming, with regard to the second part (of the century). (3) The following are some of the activities that have led to the advent of a scenario where, there is a disturbing rise in the greenhouse emissions: various agricultural practices,

Questions answering 2053 Essay Example | Topics and Well Written Essays - 500 words

Questions answering 2053 - Essay Example The firm is incorporated in one country and opens foreign subsidiaries in the countries (Cullen and Parboteeah, 2013). The existing literature identifies that globalization can take two different forms namely forced globalization and participative globalization (McCann and Acs, 2011). MNCs enter the globalization through the avenue of participative globalization. The opening of companies in foreign land has received huge boost during the past three decades and this is entirely because of globalization. It has been estimated that multinational companies comprise two-third of the global trade (McCann and Acs, 2011). Reduced cost of production, expansion of market for products and earning higher profits are driving forces to expand business. The cost of labour is considerably lower in the developing countries compared to the developed countries and this motivates firms to relocate production. When domestic markets become saturated it becomes imperative to capture other consumers and foreign expansion is a lucrative option for companies (Dunning, 2012). Difference in cultures is perhaps the most formidable challenge that has to be faced by companies in their quest for expansion. Management of interpersonal relationships in the MNCs require integrating the national culture of the managers and employees (Sweeney and McFarlin, 2014). Additionally MNCs requires modifying their products and services according to the niche taste of the masses depending on the country. For instance, when New York Fresh Deli opened franchises in Dubai, vinegar had to be removed from the salad dressings as it was considered as spirit in Dubai (Guffey and Loewy, 2010). According to Hofstede (2011) culture can be treated as mental software that affects the way in which a person thinks or behaves. Effective management of human resource is important for the MNC’s as people are often exposed to

Employee training at B&Q Plc Essay Example | Topics and Well Written Essays - 2000 words

Employee training at B&Q Plc - Essay Example There has been a various change in the employment policy at B&Q Plc. over the past decade. About a decade ago, many business analysts criticized B&Q Plc. For having a policy that encouraged to employ and retaining much older employees. At that time younger job seekers were less advantaged when they were seeking jobs at the company. The company has always considered quality of their products and services to be their first priority. Therefore, employing older employees was seen as a way through which the company could be able to get experience and skills in a single package (Saks, Haccoun& Belcourt 2010, p. 101. At that time this really worked for them especially because they were able to build a reputation that was rooted on quality. There is always some uncertainty regarding employing younger employees. Younger employees might be skilled by the obvious reason as to why employing them might not be a good idea is the fact that it might take a while before they attain the experience that the older employees have. However, the good thing is that this is a problem that can be properly solved by having a good training program. As for the case of B&Q Plc. mentoring was chosen as the most appropriate way of making sure that the company will be able to accommodate both the young and energetic employees and the old and experienced employees (Becker 1993, p. 123). This method can be said to have worked well for the company.

Examples Of The Company Suffering From Bad Publicity

Examples Of The Company Suffering From Bad Publicity Greenpeace distributed an argumentative video on YouTube about Nestlà ©s source for palm oil for their products. The targeted product was the Kit Kat bar and the video play off the Kit Kat slogan Have a break, Have a Kit Kat. Greenpeace said that Nestlà ©s source have a dirty hands in ruining a rainforests which were natural habits for orangutans. Furthermore, Greenpeaces video also imitative Kit Kats commercial by starting by a bored office worker tearing paper for his boss for hours. He pulls out a Kit Kat bar and bites into it without noticing or caring that the Kit Kat is actually a bleeding orangutan finger, and leaks blood all over his face and keyboard. In this case, Nestle took a quick action removed the video. By today technology, there is still had a way to let YouTube user repost the video. The users started reposting the video all over the internet and the more internet users repost the video all over the internet, and the more videos is taken down, the more videos will added. *What is companys brand positioning? (March 2012) http://www.nestle.com/csv/nutrition/positionedproducts Affordable and nutritious Nestle targeted customer with products that are nutritious, cheaper and tasty. Popularly Positioned Products (PPPs) supply high nutritional value by affordable cost and in suitable formats to send the needs of some 3 billion lower-income consumers worldwide. Their current PPPs spread from culinary products to beverages, to dairy and biscuit with over 400 products are sold under some global brands such as Maggie and Nescafe. These actions bring 30-40% improvement in market penetration within lower-income customers in the last 2 years and increase distribution of Maggie noodles by advertise about affordability and healthy messages. * Provide some information about a recent marketing campaign. http://www.networkworld.com/community/blog/marketing-gone-wild-candy-bars-stalk-you Nestle company launch a promotion called We will find you that find by GPS trackers which the shape alike normal chocolate bars. When a winning customer opens the wrapper, it will activates and send a message to the prize team who tracking them down within 24 hours to deliver a check for  £10,000. This chocolate product can find from KitKat Chunky, Yorkie Milk, KitKat 4 Finger and Aero Peppermint Medium. London showed off this video of Nestle using cutting edge geolocation technology to track down six lucky winners across the UK and Ireland. They believe that this promotion will particularly invoke to men, fascinating them to the chocolate singles category and thus driving increasing sales. Nestlà © Confectionery is delighted to be first to market with this highly innovative GPS for the promotion. During August 2010, Brazil was the first to use GPS, drop it into a product to track you and take marketing promotions to a whole new creepy yet innovative level. CORPORATE SOCIAL RESPONSIBILITY Corporate Social Responsibility is defined a concept which the company incorporate social and environmental concerns in business operations and interactions with stakeholders on voluntary basis. Does the company promote a positive impact through its activities on the environment, consumers, employees and communities? http://www.ukessays.co.uk/essays/communications/nestle.php Nestle shown great concern for the society though the launch of their concept of Corporate Social Responsibility in 2006, Creating Shared Value (CSR).after the launch of CSR, Nestle undertaken many projects to help the society. A great project that brought significant change to society is The Cocoa Plan project to facilitate African cocoa farmers and the society take advantage of setting market prices by growing their productivity. Nestle funded farmer schools in West Africa to learn better ways which able to produce higher quality cocoa and increase revenue. Not only that, Nestle built a development and research centre that work in hand with Nestle plant science base. Nestle as a partner of International Cocoa Initiative and the World Cocoa foundation solved problems, example child labour and lack of access of education and health such as send farmers to field schools educates the farmer the way to increase productivity and also educated of diseases and prevention ways. In this case , the increasing of income for those West African household enhance their lifestyles. Between that, the dramatically of boosting of production of cocoa increase their exports and conversely decrease their foreign owing. There are also can learn new skills, study the technology and share useful information among the locals who sent to work. http://businesscasestudies.co.uk/nestle/business-principles-in-action-nutritional-labelling/ethics-and-business-principles.html#axzz2L5lKmRxZ Nestle developed two business principles that focused on communications with consumers. One of the business principle is Nestle consumer communication should reflect moderation in food consumption and not encourage overeating especially important regarding children. Another one of the business principle is must combine the desire for healthy and balanced diets. Their advertising must not mean the reposition of meals with snack foods and heavy snacking. Nestle helps consumers recognize and understand the nutritional content of the food that they bought. This is a positive impact on the reputation of the company. Consumers can be know the Nestle behaving responsibly and communicating with them. They also facilitate and promote healthy living for their staffs. Nestle company linked to the Guideline Daily Amounts on the front of packs with the internal communication programme to tell staffs about GDAs and labeling system. In this case, it can help to motivate staffs as showed nestle care d about their well-being and their families.

Desi Arnaz :: Essays Papers

Desi Arnaz Cuban bandleader and singer-turned savvy TV mogul who, after his marriage to comedienne Lucille Ball in 1940, parlayed their successful "I Love Lucy" series into the Desilu TV production empire, which in its heyday also produced the successful and highly lucrative "The Untouchables" and "Star Trek" series. *p*Desiderio Alberto Arnaz y de Acha III was born in 1917 to wealthy Cuban landowners. His father was also the mayor of the town they lived in, but that soon changed. At the age of 16, Desi and his mother had to flee to Miami because of Batista's overthrow of the Machado Government in 1933. *P**BR*When Desi arrived in America, it was a struggle for he and his mother. But soon after he arrived, he joined the Siboney Septet at the Roney Plaza. Later, he started working with Xavier Cugat's band in 1937 and later put together his own rhumba band. His youthful good-looks and engaging presence soon won him a featured spot in the 1939 Broadway musical and theatrical version of "Too Many G irls" and the following year he was signed by RKO. On the movie set, he met his future wife, Lucille Ball. Later that year Desi and Lucy eloped to Connecticut and got married in a country club. Arnaz was featured in several films, mostly as a colorful Latin. Joining MGM, he won attention for his sole dramatic role in the war drama, "Bataan" (1942), but gave up films for touring with his successful band. The marriage was subject to the road most of the time and to Lucy's movie career. When the couple came up with the idea for a television series, they fought to do it together to save their marriage. But the network didn't think the television series would work with Desi being Cuban. But that didn't stop Lucy and Desi. In the summer of 1950, they went on tour, performing for live audiences to prove that the show would work. Well, as you know, the rest is television history!*P**BR*Desi made the first 5,000 dollars spent into millions in just four years. He convinced the show's sponsor, Phillip Morris, that Lucy having a baby on the show would give them great publicity. He was right: the birth of Little Ricky drew 44 million viewers (the swearing in of the President that year only drew 22 million), and the story made headlines everywhere across America. With Desi as a successful executive, and head of the couple's production company, DesiLu, Arnaz pioneered a new way of producing TV shows, shooting each episode of I