History of Chemistry Introduction: Humans have always been very curios creatures. The have always wondered about what they are and why they are here. Our limited knowledge of the environment has always urged for new things to be discovered. The desire to understand the world better has made people search for rational answers, for principles and laws Free History of chemistry Essays and Papers History of Chemistry. Chemistry is a branch of science that has been around for a long time. It has been here ever since Modern Chemistry: The History And History Of Chemistry. Etymology The word chemistry comes from alchemy, which referred The Learning the history of chemistry will help students understand the major topics and themes involved in this branch of science. This lesson provides a series of essay topics designed to encourage
History Of Chemistry Essay
Essay Examples, history of chemistry essay. Notions of a similar kind have been hinted at by other Greek thinkers, but ever so fully elaborated. He states that all matter is composed of eternal, indivisible, indestructible and infinitely small substances which cling together in different combinations to form the objects perceptible to us.
The Greek word for indivisible is atoms. This theory gives birth to the atom. Democratic was a Greek philosopher who lived between BC He is the Greek to whom the conception of the Atomic theory is attributed. Democratic proclaims the atom to be the simplest unit of matter.
All matter was composed of atoms. He declares the existence of only four elements: fire, air, water and earth, history of chemistry essay. All matter is made up of these four elements and matter had four properties: hot, cold, dry and wet. Greek science in Alexandria: from the 3rd century BC Classical Greece has produced a brilliant tradition of theorists, the dreamers of science.
Attracted by the intellectual appeal of good theories, they are disinclined to engage in the manual labor of the laboratory where those theories might be tested. This limitation is removed when the centre of the Greek world transfers, in the 3rd century BC, to Alexandria. In this bustling commercial centre, linked with long Egyptian traditions to skilled work in precious metals, people are interested in making practical use of History of chemistry essay scientific theory.
Forecastles that the difference in material substances is a matter of balance, then that balance might be changed. Copper might become gold. Among the practical scientists of Alexandria are men who can be seen as the first alchemists and the first experimental chemists.
Their trade, as workers in precious metals, involves melting gold and silver, mixing alloys, changing the color of metals by mysterious process. These are the activities of chemistry. The everyday items of a chemical laboratory — stills, furnaces, flasks — are all in use in Alexandria. There are strong mystical influences in Egypt, some of them deriving from Bibliographically, and this tradition too encourages experiment.
Astrologers believe in many hierarchies, among the planets in the heavens but also among metals in the earth. Lead is the lowest of the metals, gold the highest. Left to itself, out of sight in the earth, lead may slowly be transformed up the scale to achieve ultimate perfection as gold. In the early centuries, the experiments of chemistry and alchemy go hand in hand.
Beginning of the Christian Era — End of 17th Century Alchemy The Advent of the Alchemists Influenced greatly by Aristotle ideas, alchemists attempted to transmute cheap metals to gold.
This elixir of life never happened either. Alchemy in Asia: 8th — 10th century AD There are two important centers of alchemical experiment in medieval Asia.
One safeguarding the caliphate, where from the 8th century there is enthusiastic translation and study of Certifications texts, history of chemistry essay. Arab alchemists, in their pursuit of synthesized gold, make practical advances in techniques of distillation. And they identify several chemical substances. The other great centre is China, where alchemical experiments nave a slightly different purpose.
The quarry is still gold, but as an elixir of eternal life. This is the pursuit of the Dadaists one of whom describes, with gentle irony, inexperience which goes wrong in the 9th century. It is Dadaists who make the most startling chemical coverer of the period -gunpowder. Gunpowder: 10th century In about a Chinese manual on warfare is issued under the telecommuting of Military Technology. It is the first document to describe gunpowder, history of chemistry essay. This black powder, formed by pounding a mixture of saltwater, charcoal and sulfur a dangerous process if the pounding is overdoneseems to have been developed in the small chemical laboratories attached to the temples of Dishwasher research is conducted mainly on the secret of eternal life.
At this early stage in China the military use of gunpowder is limited to grenades and mobs lobbed at the enemy from catapults. Its real destructive force will only emerge when the explosion is confined, in the development of artillery, history of chemistry essay. God knows best, and so He should — since He created everything. Where practical knowledge is required, there are ancient authorities whose conclusions are accepted without question -Ptolemy in the field of astronomy,Galen on matters anatomical.
A few untypical scholars show an interest in scientific research. The 13th-century Franciscan friar Roger Bacon is the most often quoted example, but his studies include alchemy and astrology as well as optics and astronomy, history of chemistry essay.
The practical skepticism required for science must await the Renaissance, history of chemistry essay. Van Hellion: AD A book is published in Amsterdam history of chemistry essay which can be seen as a definitive turning point between alchemy and chemistry. Entitled Rotors Medicine Origin of Medicineit is the collected papers of Jan Baptists van History of chemistry essay, an aristocrat who has lived quietly on his estate near Brussels conducting scientific experiments.
Van Hellion is inclined to mysticism. But he also conducts experiments on entirely scientific principles. Some, like his famous five-year project with a willow tree, lead him to the wrong conclusion. But the method is valid. Van Hellion weighs out lbs to dried earth n, history of chemistry essay, places it in an earthenware container and plants a willow tree weighing 5 lbs.
For five years he waters the plant daily. At the end of the experiment the willow tree weighs bases and the earth, when dried, not much less than lbs. Van Hellion concludes, reasonably that the wood, bark ND leaves of the tree must be composed of water, which he therefore considers to be the chief constituent of all matter.
What van Hellion is unaware of is that the tree has also absorbed carbon and oxygen, as carbon dioxide or CA, from the air. Ironically, Van Hellion himself becomes the first scientist to postulate the existence of carbon dioxide. He burns 62 lbs of charcoal and finds that he is left with only 1 lb of ash. What has happened to the rest? Van Hellion is convinced, ahead of his time, of the indestructibility of matter. Indeed he is able to demonstrate that metal dissolved in acid can be recovered history of chemistry essay loss of weight.
So he now reasons that the missing 61 lbs have escaped in the form of an airy substance to which he gives the name gas Sylvester wood gas. The identity of this wood gas is not discovered until a century later bypasses Blackbut van Hellion is the first to have suggested the existence of gaseous substances other than air. The principles of experiment enter chemistry in the work of van Hellion, and are developed by another aristocrat fascinated by the puzzles of science — Robert Bobble.
Robert Bowie: AD The experimental methods of modern science are considerably advanced by the work of Robert Bobble during the sass. But Bobble also uses the air pump to make significant discoveries of his own — most notably that reduction in pressure reduces the boiling temperature of a liquid water boils at at normal air pressure, but at only ICC if the pressure is reduced to one tenth. Air is trapped in the closed end by a column to mercury. Bobble can snow that it TN weight of mercury is doubled, the volume of air is halved.
The Skeptical Sympathizers in Bobble is properly skeptical about contemporary theories on the nature of matter, which still derive mainly from the Greek theory four elements. His own notions are much closer to the truth. Compounds, he argues, can be broken down into their constituent elements.
In an important work of ,Experiments and Considerations Touching Colors, Bobble argues that colors have no intrinsic identity but are modifications in light fleeted from different surfaces. This is demonstrated within a few years Boonton in his work on the spectrum. As a man of his time, history of chemistry essay, Bobble is as much interested in theology as science. It comes as a shock to read his requirements for the annual Bobble lecture which he founds in his will.
The rules specifically forbid any mention of disagreement among Christian sects. Joseph Black and fixed air: AD Joseph Black presents his doctoral thesis to the university of Edinburgh in and publishes it in expanded form two years later history of chemistry essay Experiments upon Magnesia Alba, Quicklime, history of chemistry essay, and Some Other Alkaline Substances. The experiments which he history of chemistry essay are a classically complete series of compound transformations of calcium, carbon and oxygen — though it is not as yet possible to express his results in these terms.
Black has observed that if he heats chalk calcium carbonatehe gets quicklime calcium oxide and a gas, the presence of which he can identify by its weight. Unwilling as yet to speculate on its identity, he calls it fixed air — because it exists in solid form until released. As a next stage, Black demonstrates history of chemistry essay en can reverse the process. Mixing water with the quicklime, he gets a substance slaked lime which will take up the fixed air again — leaving him with his original amount of chalk and the water.
In other experiments Black is able to show that this same unknown gas, his fixed air, is produced as a result of burning charcoal, of fermentation and of breathing. He demonstrates this last point to his students by breathing through a tube into a Jar of intimate a clear solution of slaked lime.
The liquid turns cloudy as grains of chalk form in it. Blacks fixed air is the gas Sylvester which the existence has been postulated by van Hellmann century earlier. Blacks proof that such a gas exists prompts an energetic search for others. Hydrogen is identified backhanders inand oxygen almost simultaneously by Schlep and Priestley in the sass. Meanwhile Black has history of chemistry essay another important scientific principle, latent heat.
Cavendish and hydrogen: AD In Henry Cavendish presents his first paper to the Royal Society. Hydrogen has history of chemistry essay observed as a phenomenon for at least two centuries.
The 16th- century alchemist and charlatan Paralegals finds that the dissolving of a metal in acid releases a form of air which will burn. But Cavendish is the first to identify it as pacific substance. He believes that he has found the inflammable essence,phlogiston. The study of gases in the laboratory is by now a standard chemical process thanks to the pneumatic trough developed in the early part of the 18th century by Stephen Hales.
An upturned vessel, full of water, stands in a shallow trough of water. Gas is collected in the top of the vessel, history of chemistry essay, displacing water and being sealed in by it. With this device Cavendish is able to calculate the specific gravity of hydrogen.
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History of Chemistry Introduction: Humans have always been very curios creatures. The have always wondered about what they are and why they are here. Our limited knowledge of the environment has always urged for new things to be discovered. The desire to understand the world better has made people search for rational answers, for principles and laws History of Chemistry. The Greek scholar Empedocles, a Sicilian local, progresses a postulation unknown until the seventeenth century in Europe. He expresses that all issue contains four essential components earth, wind, fire, and water-in various extents Chemistry is the main incentive for the life that we live today; it has provided modern society with facilities that make our day to day lives easier. Chemistry has allowed us to understand the composition of the world. In short this branch of science has enabled us to lead a better quality of life. The beginning when did we start studying chemistry?
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