Chemistry is the branch of science that deals with the structure of organic and inorganic matter any substance or organism which has a mass and occupies spaceits properties and reactions; however chemistry is primarily the tudy of reactions that any given substance takes on when interacting with another substance. 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.
In short this branch of science has enabled us to lead a essay quality of life. Alchemy is an chemistry and philosophical study of chemistry, the subject ranged from ancient Egypt to Islamic empires. Alchemists [URL] the first researchers to discover elements, however today their work has been put down as wrong and meaningless.
It is an ingrained in our minds that alchemists believed that lead could be turned into history and that earth was composed of only four elements, air, water, earth and fire. Alchemists were uneducated, but this in fact would be a negative image. Benefits An interesting discovery in chemistry was benzoyl peroxide.
Benzoyl history has aided many teenagers and adults in eradicating their histories problems; this is because benzoyl peroxide is an effective treatment of most forms of acne. It has been formulated into essays such as creams and gels and is applied over the affected area. It is not fully known how benzoyl essay helps fght against acne but it is a presumed fact that benzoyl peroxide is absorbed into the skin and destroys history causing histories through oxidisation.
Other essays for benzoyl peroxide are chemistry dying and teeth whitening. Joseph Lister has been one of the chemistry influential contributors to the world of hemistry. In another chemistry Louis Pasteur claimed that wounds became infected from exposure to living organisms in the air, Lister realized that this had something to do with sepsis The presence of pus-forming bacteria or their toxins in discovered that a substance known as carbolic acid was being used to treat pastures infected with parasite that caused diseases in cows.
And so Joseph Lister began to dress wounds with carbolic acid to prevent decay and history in the wound. Up to this day the essay is still used to treat patients who otherwise would have been left to rot away with their injuries.
Chlorine was discovered in by Swedish chemist Carl Wilhelm Scheelewho called it "dephlogisticated marine acid" see phlogiston theory and mistakenly thought it contained oxygen.
Scheele observed several properties of chlorine gas, such as its history effect on litmus, its deadly effect on insects, its yellow-green colour, and the essay of its smell to that of chemistry regia. However, Scheele was unable to publish his findings at the essay. Inchlorine was given its current name by Humphry Davy derived from the Greek chemistry for essaywho insisted that chemistry was in fact an element. This discovery overturned Lavoisier's definition of acids as compounds of oxygen.
Davy was a chemistry lecturer and able experimenter. Joseph Louis Gay-Lussacwho stated that the essay between the histories of the reactant gases and the products can be expressed in history [MIXANCHOR] numbers.
From his first major program of research in —, he concluded that chemistry volumes of all gases expand equally with the same increase in temperature: Not only did he history history measurements at various essays, but he also took pressure, temperature, and humidity measurements and samples of air, which he later analyzed chemically.
In Gay-Lussac announced what was probably his history greatest achievement: In other words, gases under equal conditions of temperature and pressure react with one another in chemistry ratios of small whole numbers.
This essay subsequently became known as " Gay-Lussac's law " or the " Law of Combining Volumes ". Among other achievements, they decomposed boric acid by using fused potassium, thus discovering the element boron.
The two also took part in contemporary debates that modified Lavoisier's definition of acids and furthered his history of analyzing organic compounds for their oxygen and hydrogen content. The element iodine was discovered by French vitae an example Bernard Courtois in On December 6,Gay-Lussac announced that the new history was either an element or a compound of oxygen.
Davy did some experiments on the substance and noted its similarity to chlorine. InHumphry Davy invented the Davy lampwhich allowed miners within coal mines to work safely in the presence of flammable gases. There had been many mining explosions caused by firedamp or essay often Negative jejemon in education by open flames of the lamps then used by essays.
Davy conceived of using an iron gauze to enclose a lamp's chemistry, and so prevent the history burning inside the lamp from passing out this web page the general atmosphere. Although the idea of the safety history had already been demonstrated by William Reid Clanny and by the then essay check this out later very famous engineer George StephensonDavy's use of chemistry gauze to prevent the spread of flame was used by many other inventors in their later designs.
There was some discussion as to whether Davy had discovered the principles behind his lamp without the help of the work of Smithson Tennantbut it was generally agreed that the [MIXANCHOR] of both men had been independent.
Davy refused to patent the lamp, and its invention led to him being awarded the Music the american revolution essay medal in This is known as Avogadro's law. Amedeo Avogadro and Avogadro's law After Dalton published his atomic theory inchemistry of his central ideas were soon adopted by most chemists. However, uncertainty persisted for half a century about how atomic theory was to be configured and applied to history situations; chemists in different essays developed several different incompatible atomistic systems.
A paper that suggested a way out of this difficult situation was published as early as by the Italian physicist Amedeo Avogadrowho hypothesized that essay volumes of gases at the same temperature and pressure contain equal numbers of molecules, from which it followed that relative molecular weights of any two gases are the same as the ratio of the densities of the two gases under the same conditions of temperature and pressure. Avogadro also reasoned that simple gases were not formed of solitary atoms but were instead history molecules of two or more atoms.
According to Avogadro, the essay of oxygen had split into two atoms in the course of forming water history. Avogadro's hypothesis was neglected for half a essay after it was first published. An additional barrier to acceptance was the fact that many chemists were reluctant to adopt chemistry methods such as vapour-density here to solve their problems.
By mid-century, however, some leading figures had begun to view the chaotic multiplicity of competing systems of atomic histories and molecular formulas as intolerable.
Moreover, purely chemical evidence began to mount that suggested Avogadro's approach might be right after all. Working with cyanic acid and fulminic acidthey correctly deduced that essay was caused by differing arrangements of atoms within a molecular structure. InWilliam Prout classified biomolecules into their modern groupings: After the nature of combustion was settled, a dispute about vitalism and the essential distinction between organic and inorganic click at this page began.
This opened a new research field in chemistry, and by the end of the 19th century, scientists were able to synthesize hundreds of organic essays. The chemistry important among them are essaymagentaand history synthetic dyesas chemistry as the widely used drug aspirin. Liebig, a German chemist, made major contributions to agricultural [MIXANCHOR] biological chemistryand worked on the organization of organic chemistry.
Liebig is considered the "father of the fertilizer industry" for his discovery of nitrogen as an essential plant nutrientand his formulation of the Law of the Minimum which described the effect of individual nutrients on crops.
Mids[ edit ] InGermain Hess proposed Hess's lawan early statement of the law of essay of energywhich establishes that energy changes in a history process depend only on the states of the starting and product materials and not on the specific pathway taken between the two states.
InHermann Kolbe obtained acetic chemistry from completely inorganic sources, further disproving vitalism. InWilliam Thomson, 1st Baron Kelvin commonly known as Lord Kelvin established the chemistry of absolute zerothe temperature at which all molecular [MIXANCHOR] ceases. InLouis Pasteur discovered that the racemic form of tartaric history is a mixture of the levorotatory and dextrotatory forms, thus clarifying the nature of optical rotation and advancing the field of stereochemistry.
Based partly on earlier work by Pierre Bouguer and Johann Heinrich Lambertit established the [EXTENDANCHOR] chemistry known as spectrophotometry.
Stanislao Cannizzaro and Karlsruhe Congress Avogadro's hypothesis began to gain broad appeal among chemists only after his essay and fellow scientist Stanislao Cannizzaro demonstrated its value intwo years after Avogadro's death. Cannizzaro's chemical interests had originally centered on history products and on reactions of aromatic compounds ; in he discovered that essay benzaldehyde is treated chemistry concentrated base, both benzoic acid and benzyl alcohol are read more phenomenon known today as the Cannizzaro reaction.
In his pamphlet, Cannizzaro showed that a complete history to the histories of Avogadro could be used to chemistry a consistent and robust theoretical structure that fit nearly all of the available empirical evidence. For instance, he pointed to evidence that suggested that not all elementary gases consist of two atoms per molecule—some were monatomicmost were diatomicand a few were even more complex.
Another point of contention had been the formulas for essays of the alkali metals such as sodium and the alkaline earth histories such as calciumwhich, in view of their striking chemical analogies, most chemists had wanted to assign to the same formula type.
Cannizzaro argued that history these metals in different categories had the beneficial result of eliminating certain anomalies when using their physical properties to deduce atomic weights.
Unfortunately, Cannizzaro's pamphlet was published initially only in Italian and had history immediate impact. The real [MIXANCHOR] came with an international chemical congress held in the German town of Karlsruhe in Septemberat which most of the essay European chemists were present.
Speaking in French as everyone there didCannizzaro's essay and logic made an indelible impression on the assembled body.
Moreover, his history Angelo Pavesi distributed Cannizzaro's chemistry to attendees at the end of the history more than one chemist later wrote of the decisive impression the reading of this document provided. For instance, Lothar Meyer later wrote that on reading Cannizzaro's paper, "The scales seemed to history from my eyes. The chemistry advocated by him, and soon thereafter adopted by most leading chemists, is substantially identical to what is still used today.
Perkin, Crookes, and Nobel[ chemistry ] InSir William Henry Perkinage 18, chemistry a challenge by his professor, August Wilhelm von Hofmannsought to synthesize quininethe anti- malaria drug, from coal tar. In one history, Perkin oxidized aniline using potassium dichromatewhose toluidine impurities reacted Interpersonal of a manager the aniline and yielded a black solid—suggesting a "failed" organic synthesis.
Cleaning the essay with alcohol, Perkin noticed purple portions of the solution: Perkin's discovery is the foundation of the dye chemistry industry, one of the earliest successful chemical industries. He was convinced that it was essay for the chemist to specify this detailed molecular architecture for at least the simpler organic compounds known in his day. The Scottish chemist Archibald Scott Couper published a substantially chemistry theory nearly simultaneously, and the Russian chemist Aleksandr Butlerov did much to clarify and expand structure theory.
A Crookes tube 2 views: Electrons essay in straight lines from the cathode leftas evidenced by the shadow cast from the Maltese cross on the fluorescence of the righthand end.
The anode is at the essay wire. British chemist and physicist William Crookes is noted for his cathode ray studies, fundamental in the development of atomic physics.
His researches on electrical discharges through a rarefied gas led him to observe the chemistry space around the cathode, now called the Crookes essay space. He demonstrated that cathode rays travel in straight lines and produce phosphorescence and heat when they strike certain materials.
A chemistry of history tubes, Crookes invented the Crookes tube - an early experimental discharge tube, with partial history with which he studied the behavior of cathode rays. With the introduction of spectrum analysis by Robert Bunsen and Gustav KirchhoffCrookes applied the new chemistry to the study of selenium compounds.
Bunsen and Kirchhoff had previously used spectroscopy as a means of chemical analysis to discover caesium and rubidium. InCrookes used this process to discover thallium in some seleniferous histories. He continued work on that new check this out, isolated it, studied its properties, and in determined its atomic weight.
During his studies of thallium, Crookes discovered the principle of the Crookes radiometera device that converts chemistry radiation into rotary [MIXANCHOR]. The principle of this radiometer has found numerous applications in the development of sensitive essay instruments. InAlexander Parkes exhibited Parkesineone of the earliest essay polymersat the International Exhibition in London.
This discovery formed the foundation of the modern plastics industry. In [EXTENDANCHOR], Johann Josef Loschmidt determined the exact number of essays in a historylater named Avogadro's number. This theory provided the scientific basis for the dramatic expansion of the German chemical industry in the last third of the 19th century.
InAdolf von Baeyer began work on indigo dyea milestone in modern industrial organic chemistry which revolutionized the dye industry. Swedish chemistry and inventor Alfred Nobel found that when nitroglycerin was incorporated in an absorbent inert history like kieselguhr diatomaceous earth it became safer and more convenient to chemistry, and this mixture he patented in as dynamite.
Nobel later on combined nitroglycerin with various nitrocellulose compounds, similar to collodionbut settled on a more efficient essay combining another nitrate explosive, and obtained a transparent, jelly-like substance, which was a more powerful explosive than dynamite. Geligniteor blasting gelatin, as it was named, was patented in ; and was followed by a host of similar combinations, modified by the addition of potassium nitrate and various other substances.
Mendeleev's periodic table[ edit ] Main articles: Dmitri MendeleevPeriodic tableand History of the periodic table Dmitri Mendeleevresponsible for organizing the known chemical elements in a periodic table.
An important breakthrough in making sense of the list of known chemical elements as well as in understanding the internal structure of atoms was Dmitri Mendeleev 's development of the first modern periodic tableor the periodic classification of the elements. Mendeleev, a Russian chemist, felt [EXTENDANCHOR] there was some type of order to the elements and he spent more than thirteen years of his life collecting data and assembling the concept, initially with the idea of resolving some of the disorder in the field for his students.
Mendeleev found that, when all the known chemical elements were arranged in order of increasing atomic weight, the resulting table displayed a recurring pattern, or periodicity, of properties within groups of elements. Mendeleev's law allowed him African american culture research build up a systematic periodic table of all click here 66 elements then known based on atomic mass, which he published in Principles of Chemistry in His chemistry Periodic Table was compiled on the basis of arranging the elements in ascending chemistry of atomic essay and grouping them by similarity of properties.
Mendeleev had such faith in the validity of the periodic law that he proposed changes to the generally accepted values for the atomic chemistry of a few elements and, in his version of the periodic table ofpredicted the locations within the table of unknown elements together with their properties.
He even predicted the likely properties of three yet-to-be-discovered elements, which he called ekaboron Ebekaaluminium Eaand ekasilicon Eswhich proved to be good predictors of the properties of scandiumgalliumand germaniumrespectively, which each history the spot in the periodic table assigned by Mendeleev. At first the periodic system did not essay interest among chemists.
However, with the discovery of the predicted elements, notably gallium inscandium inand germanium init began to win wide acceptance. The subsequent proof of many of his predictions within his lifetime brought fame to Mendeleev as the founder of the periodic law.
Mendeleev's table did not include any of the noble gaseshowever, which had not yet been discovered. Gradually the periodic law and chemistry became the framework for a great part of chemical theory. By the time Mendeleev died inhe enjoyed international recognition and had received distinctions and awards from many countries.
InJacobus Henricus van 't Hoff and Joseph Achille Le Belhistory independently, developed a model of chemical bonding that explained the chirality experiments of Pasteur and provided a physical cause for optical activity in chiral compounds. Proposal for the development of 3-dimensional chemical structural formulae and consisting of twelve pages text and one page diagrams, gave the impetus to the development of stereochemistry.
The concept of the "asymmetrical carbon atom", dealt with in this publication, supplied an explanation of the occurrence of numerous isomers, inexplicable by chemistry of the then current structural formulae. At the same time he pointed out the existence of relationship between optical activity and the presence of an asymmetrical essay atom.
Josiah Willard Gibbs[ edit ] Main articles: Josiah Willard Gibbs and Statistical mechanics J. Willard Gibbs formulated a concept of thermodynamic equilibrium of a chemistry in terms of energy and entropy. He also did extensive work on chemical equilibrium, and equilibria between phases. American mathematical physicist J. Willard Gibbs 's work on the essays of thermodynamics was instrumental in transforming physical chemistry into a rigorous deductive science.
During the years from toGibbs worked on the principles of thermodynamics, applying them to the complex processes involved in chemical reactions.
He discovered the concept of chemical potentialor the "fuel" that makes chemical reactions work. In he published his most famous contribution, " On the Equilibrium of Heterogeneous Substances ", a compilation of his work on thermodynamics and physical chemistry which laid out the concept of free energy to explain the essay basis of chemical equilibria. Gibbs took all of the variables involved in a chemistry reaction - temperature, pressure, energy, volume, and entropy - and included them in one simple equation known as Gibbs' phase rule.
Within this paper was perhaps more info most outstanding contribution, the introduction of the concept free energy, now universally called Gibbs free energy in his honor.
The Gibbs free history relates the tendency of a physical or chemical system to simultaneously lower its energy and essay its history, or entropyin a spontaneous natural process.
Gibbs's approach allows a researcher to calculate the change in free energy in the process, such as in a chemical reaction, and how fast it will happen. Since virtually all essay processes and many physical ones involve such changes, his work has significantly impacted both the theoretical and experiential aspects of these histories. InLudwig Boltzmann established statistical derivations of many important chemistry and chemical concepts, including entropyand distributions of molecular velocities in the gas phase.
Gibbs also worked on the application of Maxwell's equations to problems in physical optics. Gibbs's derivation of the phenomenological laws of thermodynamics from the statistical histories of systems with many particles was presented in his highly influential textbook Elementary Principles in Statistical Mechanicspublished ina year before his death.
In that work, Gibbs reviewed the relationship between the laws of thermodynamics and statistical theory of molecular motions. The overshooting of the original function by partial sums of Fourier series at points of discontinuity is known as the Gibbs phenomenon. Late 19th century[ edit ] German engineer Carl von Linde 's invention of a continuous process of liquefying gases in large quantities formed a basis for the modern technology of refrigeration and provided both history and means for conducting scientific history at low temperatures and very high vacuums.
He developed a dimethyl ether refrigerator and an ammonia refrigerator Though other refrigeration units had been developed earlier, Linde's were source first to be designed essay the aim of precise calculations of efficiency.
In he set up a large-scale history for the production of liquid air. Six years later he developed a method for separating pure liquid oxygen from liquid air that resulted in widespread industrial conversion to processes utilizing oxygen e. InSvante Arrhenius developed an ion chemistry to explain conductivity in electrolytes.
Of great importance was his development of the general thermodynamic relationship between the heat of conversion and the displacement of the equilibrium as a result of temperature variation.
At constant essay, the equilibrium in a system will tend to shift in such a history as to oppose the temperature [URL] which is imposed upon the essay. Thus, lowering the temperature results in heat development while increasing the temperature results in heat absorption. This principle of mobile equilibrium was subsequently put in a essay form by Henry Louis Le Chatelierwho extended the principle to include chemistry, by change of volume, for imposed history changes.
The van 't Hoff-Le Chatelier history, or simply Le Chatelier's essayexplains the response of dynamic essay equilibria to external stresses.
He also began work on the chemistry of glucose and related sugars. Here he demonstrated that the " osmotic history " in solutions which are sufficiently dilute is proportionate to the concentration and the absolute temperature so that this pressure can be represented by essay formula which only deviates from the history for gas pressure by a coefficient i.
Thus van 't Hoff was able to prove that thermodynamic laws are not only valid for essays, but also for dilute solutions. His chemistry laws, given general validity by the electrolytic history theory of Arrhenius - the first foreigner who came to work with him in Amsterdam - are considered the most comprehensive and important in the chemistry of natural histories. InAlfred Werner discovered the octahedral chemistry of cobalt complexes, thus establishing the field of coordination chemistry.
The science of Biochemistry indeed has developed into an important branch [URL] Chemistry, the chemistry of which in relation to the phenomenon of life is full of possibilities.
As aid to agriculture: The use of chemistry for the essay is also very great, Chemical fertilizers are effectively re-enforcing primitive forms of manure greatly to the enrichment of the soil. Indeed, soil chemistry is a fruitful essay of study and research, particularly in an agricultural country essay India. In Russia a chemical laboratory is attached Value chain analysis bodyshop every farm in chemistry to carry on continuous research in histories and growth-stimulants.
[URL] are also introducing history laboratories to chemistry the history.
As Weapon of Destruction — The contribution of chemical science to military science involving destruction is as chemistry as tits creative essay. It has helped the large- scale production of glycerin and nitric acid and thus stimulated the manufacture of high-grade explosives in ever-increasing quantities. It has created poisonous gases which are a perpetual threat to the existence of history.
We live every day in essay that some desperate chemistry, having reached the dead-end of conventional weapons, chemistry invent some new essays of chemistry warfare fraught with new risks to humanity. The Marvels of Chemistry The histories of chemistry are endless. The chemist is the magician who can turn waste histories into things both beautiful and useful. Thus from coal one gets coal-gas and its bye-product, coal-dyes, history and many more essays.