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Discoveries in the scientific revolution
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Discoveries in the scientific revolution
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In 1817, an aging Swedish chemist was pouring over his work on a late afternoon in Stockholm, Sweden. He was analyzing a strange ore named Petalite that had been procured from an island off the coast of Sweden called Utö. The ore Petalite (which is now recognized to be LiAl(Si2O5)2) had been discovered by a Brazilian scientist, José Bonifácio de Andrada e Silva towards the end of the 18th century on a visit to Sweden. This Swedish scientist, Johann August Arfvedson, detected traces of an unknown substance in his sample of Petalite. This was the first discovery of Lithium.
From the Greek word "lithos" meaning "stone", it was so named due to the fact that it was discovered from a mineral source; whereas the other two common Group 1 elements, Sodium and Potassium, were found in plant sources. Its symbol, Li, was taken directly from its name. Soon after stumbling upon Lithium, Arfvedson also found traces of the metal in the minerals Spodumene and Lepidolite. In 1818, C.G. Gmelin discovered that Lithium salts color flames a bright red. Neither, Gmelin or Arfvedson, however, were able to isolate the element itself from the Lithium salts. They both tried to reduce the oxide by heating it with Iron or Carbon, but neither met with the success of W.T. Brande and Sir Humphrey Davy. They managed to perform the first isolation of elemental Lithium by the electrolysis of Lithium oxide. Electrolysis is a chemical reaction, which is brought about by the passage of current from an external energy source such as a battery. In 1855, the scientists Bunsen and Mattiessen isolated larger quantities of the metal by electrolysis of Lithium chloride.
Each scientist or team of scientists had so much trouble reducing the Lithium compounds because Lithium does not exist in its elemental form in nature. It combines very easily with other elements. Lithium is a soft silvery-white lustrous metal, which can be easily cut with a knife, and it is the lightest of all known metals. It is highly reactive with water and air, and tarnishes readily when exposed to the latter due to a formation of a layer of Lithium suboxide on its surface. Because of its high rate of reaction to air, it must be stored under liquid paraffin, oil, or kerosene, which contain no air, to prevent oxidation. Lithium is detected in its compounds by the characteristic red coloration that it imparts to flames when burned, as Gmelin detected, and by spectroscopic methods.
Sulfur Natarsha Harris Introduction to Chemistry Professor Michael Jones June 7, 2017. Sulfur goes back to the ancient times, but it was called brimstone. In 1979, a French chemist named Antoine Lavoisier recognized sulfur was an element and added it to his list of elements. The element sulfur is considered a nonmetal and is the 10th most abundant element in the universe. On the periodic table, sulfur is in group sixteen
Although some of the elements have been known for thousands of years, our understanding of many elements is still young. Mendeleev’s first Periodic Table contained only 63 elements, and about that many were discovered in the following 100 years. Just like countries, emperors, philosophers, and cities, elements have histories, too.“The Disappearing spoon” by Sam Kean, is a detailed history of the elements on the Periodic Table. Kean does a important job of telling every single element’s journey throughout the history of mankind: from the earliest times, when chemistry was intermingled with alchemy, to these days of modern chemistry. For example: Thallium is considered the deadliest element, pretending to be potassium to gain entry into our cells where it then breaks amino acid bonds within proteins. The CIA once developed a plan to poison Fidel Castro by dosing his socks with thallium-tainted
Edgar Allan Poe created a mysterious story about what "The Tell-Tale Heart" actually meant. The narrator had problems with the old man because he was ",... with the eye of a vulture,..." (P.23). The narrator focused all of his attention to the old man's eye because in the narrator's head it was his main reason as to why he, ",... dismembered the corpse...," (p.25) and, ",... cut off the head and the arms and the legs...," (p.25). Further into the story the narrator hears, ",... a low, dull, quick sound..," (p.24); a sounds that, ",... a watch makes when enveloped in cotton...," (p.24). The narrator thinks that the sound was the beating of the old man's heart; also thinking that the beating of the heart also resembled, "..., the beating
Strontium was discovered by Adair Crawford, an Irish chemist, in 1790 while studying the mineral witherite (BaCO3). When he mixed witherite with hydrochloric acid (HCl), he did not get the results he expected. He assumed that his sample of witherite was contaminated with an unknown mineral, a mineral he named strontianite (SrCO3). Strontium was first isolated by Sir Humphry Davy, an English chemist, in 1808 through the electrolysis of a mixture of strontium chloride (SrCl2) and mercuric oxide (HgO). Strontium reacts vigorously with water and quickly tarnishes in air, so it must be stored out of contact with air and water. Due to its extreme reactivity to air, this element always naturally occurs combined with other elements and compounds. Strontium is very
Throughout Poe’s short story he showed examples of iconography and how they showed throughout the story. In the story an example of iconography would be when the narrator killed the old man that he was taking care of, although he had done nothing to the narrator. Another prime example would be the old man’s “Evil Eye” (Poe) as described by the narrator in Poe’s story. The evil eye is what drove the narrator mad and is what led him to kill the old man at the end of the novel. Throughout most horror genre stories the person that commits the crime is usually mentally unstable and spends their time throughout the story fighting with their unstable mind. This is the same case throughout The Tell Tale Heart; the narrator throughout the story tried to justify his insanity but then lost it all at the end and turned himself in to the
Lithium has an atomic number of 3, and an atomic weight of 6.94. In general, lithium is more stable than hydrogen, and slightly less stable than nitrogen, carbon, and oxygen. When looking at chemical ion properties, it is useful to consider three main characteristics: the size, or radius, of the ion, the charge, and the ion's electron affinity. Lithium has a similar charge to radius ratio to that of magnesium, which is in group IIA of the periodic table, and so chemists say that the two elements are "chemically similar.
Edgar Allan Poe’s “The Tell-Tale Heart” is the story of the narrator and his decision and act to kill an old man with whom he lived. The narrator and the old man are never named throughout the story, neither are any supporting character such as the neighbors or the policemen. This aspect of the story gives the characters anonymity and takes the reader into the story, even calling them out at various points throughout. The narrator in this story is not given a history or even a description. His actions and thoughts through the story, lead the reader to believe that he is partially, if not wholly, insane. The recurring elements that lead to this conclusion are the narrator’s overwhelming paranoia, his fixation with the old man’s eye, and his
Like many of Poe's other works, the Tell-Tale Heart is a dark story. This particular one focuses on the events leading the death of an old man, and the events afterwards. That's the basics of it, but there are many deep meanings hidden in the three page short story. Poe uses techniques such as first person narrative, irony and style to pull off a believable sense of paranoia.
Faraday's work on the liquefaction of gases came at a time when the Royal Institution was experiencing lean times and researchers had been forced to turn their attention towards the commercial aspects of science in order to survive. In between working on steel for surgical instruments and improving the manufacture of glass for optics, Faraday continued his research. After fruitlessly heating gases in an attempt to liquefy them, Faraday chan...
This is the most common battery that people use today like Energizer or Duracle batteries. The most common form of a primary cell is the Leclanche cell, invented by a French chemist Georges Leclanche in the 1860s. The electrolyte for this battery consisted of a mixture of ammonium chloride and zinc chloride made into a paste. The negative electrode is zinc, and is the outside shell of the cell, and the positive electrode is a carbon rod that runs through the center of the cell. This rod is surrounded by a mixture of carbon and manganese dioxide. This battery produces about 1.5 volts.
Lithium Though the drug lithium is used for a number of disorders ranging from acute depression to eating and personality disorders (Paykel, 1992), it's primary use is for bipolar disorder, also known as manic depression. Patients with bipolar disorder "between two poles: depression and its opposite, mania" (Kalat,2004), often with periods of normal behavior in between (Jamison,1993). In addition, the patient is also prone to "mixed episodes" in which symptoms of both mania and depression are present. Intensity of these episodes can range from mild to dangerous, as in the case of a manic depressive mother who severed the arms of her 10 month old daughter (Associated Press, 2005).
When one thinks about women, the same basic thoughts always cross through men's mind. Too many men fit women into the same standard roles of cooking, cleaning, and catering to men. Historically throughout time the role of a woman has been lesser than that of man. Those thoughts have progressively changed with time, but have yet to reach the equality sought out by every woman. Thoughts such as those mentioned above are prevalent in literature, with most female characters following the same mold of traits and intelligence in every novel. Women historically have had to conform to specific stereotypical roles, which are often reflected in literature.
The true beginnings of the modern periodic table are found in 1669 when alchemist Hennig Brand became the first person to discover an element, phosphorus. This was accomplished accidentally through an alchemical process using urine meant to produce the fabled philosopher’s stone that was highly sought after during the time period. The actual chemical process that occurred involved the reaction of sodium phosphate and organic compounds found in urine at the high heat at which brand was boiling the urine. This reaction produced carbon monoxide and elemental phosphorus which then condensed and solidified in the form of the white phosphorous allotrope, which has a tetrahedral structure, is insoluble in water, and is highly thermodynamically unstable. He named the element, though he was not aware it was an element at the time, phosphorous meaning “light-bearing” as white phosphorous glows strongly when it is exposed to air. A few years later, English alchemist and scientific investigator Robert Boyle was able to independently isolate phosphorus through an improved process by adding sand to the urine causing a reaction in which sodium phosphate and carbon from the urine reacted with silica forming sodium metasil...
This sexism can be seen in the gender lines throughout the Harry Potter series. The Harry Potter series, by J.K. Rowling, follows a young boy named Harry Potter who learns he is a wizard and goes to Hogwarts School of Witchcraft and Wizardry. Harry is known as "The Boy Who Lived" after surviving an attack from the Dark Lord, Lord Voldemort. The series follows Harry and his friends, Ron and Hermione, on their years at Hogwarts and culminates in fight between Harry and Lord Voldemort. Despite being written in the late 20th and early 21st century, Harry Potter continues sexism which the series portrays through its female characters of Hermione Granger and Ginny Weasley. Hermione Granger is a witch Harry meets on his way to Hogwarts. Hermione is by far the brightest student at Hogwarts and is considered a "know-it-all". Despite being the smartest student at Hogwarts, Hermione 's abilities are seen as secondary to the one of the boy 's. The boys are seen as the brave and strong ones while the girls are always seeking for help. In the first book, Harry Potter and the Sorcerer 's Stone, after a troll gets lose in the school, Hermione is seen "shrinking against the wall ... looking as if she was about to faint." (Rowling, "HP and the Sorcerer 's Stone" 140) Harry and Ron then save her from the troll before anyone is hurt. Throughout the book, Hermione is seen as only good for her book smarts despite being an excellent witch. Hermione has to prove herself to Harry and Ron and they only appreciate her for her knowledge. Hermione most likely does not need to the help of Harry and Ron, especially since the spell Ron used to save her from the troll was the one she taught to Ron. It is a sexist notion that the girl 's are always the "damsel-in-distress" and are not able to save themselves. This could occur since the story is seen through Harry 's eyes which relegates Hermione to