Percent Mass of Copper in a Penny Introduction The purpose of this lab is to determine the percent mass of Cu in a penny and see if the fabricator that makes the planchets for the government is using the correct amounts of Cu in the pennies. The composition of a standard penny is 97.5% Zn and 2.5% Cu. In the lab we will be using Beer’s Law (A=elc+b where A is solution absorbance‚ e is a constant called molar absorbency‚ l is the length in cm‚ and c is the concentration). Using Beer’s Law in this
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In the Penny Cleaning Lab‚ my hypothesis‚ which stated that the lemon juice would be the best at cleaning the penny since it is an acid and acids are particularly good at cleaning metallic substances‚ was indeed valid. First‚ we started out with 1mL solutions of all the substances in the test tray. We dipped the pH paper in each solution for about a second and recorded the pH level for each substance. Before starting‚ we noticed that all the pennies were in some shade of brown‚ which I predicted
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Percent Composition of a Penny Background Information: Post-1983 pennies have a copper jacket and a zinc core. We hope to determine the percent composition of these two metals. This will be done by reacting the zinc with hydrochloric acid to form zinc ions in a single replacement reaction. The acid reacts with the zinc but not copper. The reaction of zinc metal with the hydrochloric acid (HCl) produces zinc chloride and hydrogen gas. Safety: Wear your safety goggles and apron If you spill Hydrochloric
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JC Penny On April 14‚ 1902 James Cash Penney the founder and two partners opened the Golden Rule dry-goods store in the small town of Kenner‚ Wyoming. In 1907 Penney bought out his original partners and took on new ones‚ beginning with Earl Corder Sams. When the firm was incorporated on January 17‚ 1913 as JC Penny Stores Company‚ there were 34 stores in the American West. Penney then moved the company’s main headquarters to New York. Today Penny’s is engaged in marketing apparel‚ home furnishings
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Koko was a Gorilla that was trained sign language at an early age by her primary caregiver Penny. Penny performed an experiment‚ testing to see if primates like gorillas can communicate in sign language with humans. The reason Koko was so special because she is the longest animal study in history. It infatuated the public when Koko was first in the public eye on the cover of National geographic holding kittens. Koko changed how people viewed animals‚ and got people to their emotions. Before this
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Penny Press Until the early 1800’s‚ newspapers in England and America were expensive and therefore exclusive to the wealthy and literate minority. On average‚ newspapers would cost around six cents per issue and were usually sold through subscription only. Readers would have to pay for a years’ worth of newspapers when first signing up for a subscription‚ and that cost could be a middle-class worker’s week’s wage. Most people could not afford newspapers and therefore could not receive daily news
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English 102 29 March 2012 “Texting While Driving: To Ban or Not to Ban?” Adults and teenagers are making a choice everyday to take their eyes off the road‚ their minds off of driving‚ and their hands off the wheel when they text and drive. The dangers of texting while driving are known nationwide‚ but the numerous deaths and accidents don’t seem to be stopping anyone from texting while behind the wheel. Several major corporations have launched campaigns to educate the public about
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Penny Siopis is a South African Visual Artist that focuses on the hardships that people go through in her art and she tries to understand different people by putting herself in their shoes when she works on a particular artwork. I have chosen her for my essay as she is an inspirational artist that looks at art from a unique and honest point of view . Penny Siopis was born in 1953 in the small town of Vryburg in the Northern Cape Province. She studied Fine Arts at Rhodes University and Portsmouth
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The penny has served as a trademark for America since 1793 and it has helped us succeed in many ways throughout American history. The U.S. continues to draw strength from its history and honored traditions. Therefore‚ preserving these traditions is vital to the continued greatness of our country. The U.S. should not abolish the penny because it is valuable to the economy‚ significant to society‚ and an important tradition to continue. Simply put‚ the penny is far too valuable economically and
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* “ A penny saved is a penny earned.” People do not realize that their is a history behind the changes of the penny. For instance Americans wanted to honor Lincoln’s birthday‚ but some Americans complained about the initials being too big‚ another reason for change was during World War II America needed supplies to use for battle. There is a history behind the penny that many people are unaware of. To begin with‚ the penny was changed due to Lincoln’s birthday. According to the text‚ “The strong
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