He compiles the first complete at that time list of elements, discovered and named oxygen and hydrogen, helped develop the metric system, helped revise and standardize chemical nomenclature and discovered that matter retains its mass even when it changes forms. Another popular choice for the title of Father of Chemistry is Jabir ibn Hayyan, a Persian alchemist living around AD who applied scientific principles to his studies. Alchemy was that branch of Chemistry which studied the hidden sprit of the elements.
The history of chemistry is intertwined with the history of thermodynamics, especially through the work of Willard Gibbs. The idea of a drug appears from the ancient Indian Vedas from before BC. The Chinese Alchemy believed that there were five elements, wood, fire, earth, metal and water, and these were linked to five colors, five directions and to five metals, gold, silver, leads, copper and iron.
As a result, every Chinese alchemical technique involved repeating stages five times. However, the publisher has asked for the customary Creative Commons attribution to the original publisher, authors, title, and book URI to be removed. Additionally, per the publisher's request, their name has been removed in some passages. More information is available on this project's attribution page. For more information on the source of this book, or why it is available for free, please see the project's home page.
You can browse or download additional books there. To download a. It was not until the era of the ancient Greeks that we have any record of how people tried to explain the chemical changes they observed and used.
At that time, natural objects were thought to consist of only four basic elements: earth, air, fire, and water. Then, in the fourth century BC, two Greek philosophers, Democritus and Leucippus, suggested that matter was not infinitely divisible into smaller particles but instead consisted of fundamental, indivisible particles called atoms The fundamental, individual particles of which matter is composed. Unfortunately, these early philosophers did not have the technology to test their hypothesis.
They would have been unlikely to do so in any case because the ancient Greeks did not conduct experiments or use the scientific method. They believed that the nature of the universe could be discovered by rational thought alone. Over the next two millennia, alchemists , who engaged in a form of chemistry and speculative philosophy during the Middle Ages and Renaissance, achieved many advances in chemistry.
Their major goal was to convert certain elements into others by a process they called transmutation The process of converting one element to another. Figure 1. In particular, alchemists wanted to find a way to transform cheaper metals into gold. Although most alchemists did not approach chemistry systematically and many appear to have been outright frauds, alchemists in China, the Arab kingdoms, and medieval Europe made major contributions, including the discovery of elements such as quicksilver mercury and the preparation of several strong acids.
Alchemy was a form of chemistry that flourished during the Middle Ages and Renaissance. Although some alchemists were frauds, others made major contributions, including the discovery of several elements and the preparation of strong acids. The 16th and 17th centuries saw the beginnings of what we now recognize as modern chemistry.
During this period, great advances were made in metallurgy , the extraction of metals from ores, and the first systematic quantitative experiments were carried out. In , the Englishman Robert Boyle —91 published The Sceptical Chymist , which described the relationship between the pressure and the volume of air. More important, Boyle defined an element as a substance that cannot be broken down into two or more simpler substances by chemical means.
This led to the identification of a large number of elements, many of which were metals. Ironically, Boyle himself never thought that metals were elements. In the 18th century, the English clergyman Joseph Priestley — discovered oxygen gas and found that many carbon-containing materials burn vigorously in an oxygen atmosphere, a process called combustion The burning of a material in an oxygen atmosphere.
Priestley also discovered that the gas produced by fermenting beer, which we now know to be carbon dioxide, is the same as one of the gaseous products of combustion. After he fell into a vat of fermenting beer, brewers prohibited him from working in their factories. Although Priestley did not understand its identity, he found that carbon dioxide dissolved in water to produce seltzer water.
In essence, he may be considered the founder of the multibillion-dollar carbonated soft drink industry. Priestley was a political theorist and a leading Unitarian minister. All matter is made up of these four elements and matter had four properties: hot, cold, dry and wet. Influenced greatly by Aristotle's ideas, alchemists attempted to transmute cheap metals to gold.
The substance used for this conversion was called the Philosopher's Stone. Despite the alchemists' efforts, transmutation of cheap metals to gold never happened within this time period.
Alchemists not only wanted to convert metals to gold, but they also wanted to find a chemical concoction that would enable people to live longer and cure all ailments. This elixir of life never happened either.
The disproving of Aristotle's four-elements theory and the publishing of the book, The Skeptical Chemist by Robert Boyle , combined to destroy this early form of chemistry.
Johann J. Beecher believed in a substance called phlogiston. When a substance is burned, phlogiston was supposedly added from the air to the flame of the burning object. In some substances, a product is produced. For example, calx of mercury plus phlogiston gives the product of mercury. Charles Coulomb discovered that given two particles separated by a certain distance, the force of attraction or repulsion is directly proportional to the product of the two charges and is inversely proportional to the distance between the two charges.
Joseph Priestley heated calx of mercury, collected the colorless gas and burned different substances in this colorless gas. Priestley called the gas "dephlogisticated air", but it was actually oxygen. It was Antoine Lavoisier who disproved the Phlogiston Theory. He renamed the "dephlogisticated air" oxygen when he realized that the oxygen was the part of air that combines with substances as they burn.
John Dalton publishes his Atomic Theory which states that all matter is composed of atoms, which are small and indivisible. Modern Chemistry or. Heinrich Geissler creates the first vacuum tube. William Crookes made headway in modern atomic theory when he used the vacuum tube made by Heinrich Geissler to discover cathode rays.
Crookes created a glass vacuum tube which had a zinc sulfide coating on the inside of one end, a metal cathode imbedded in the other end and a metal anode in the shape of a cross in the middle of the tube.
When electricity was run through the apparatus, an image of the cross appeared and the zinc sulfide glowed. Crookes hypothesized that there must have been rays coming from the cathode which caused the zinc sulfide to fluoresce and the cross to create a shadow and these rays were called cathode rays.
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