Learn about Chemistry

Engine Chemistry

2008-10-23T20:43:00.000-07:00

Have you ever wondered whether there is a better chemical reaction to power engines than the hydrocarbon one. One that has common easily obtained reactants, which are safe, cheap and have no nasty byproducts. This was a question I pondered even when I was at high school.

First just considering the hydrocarbon reaction central to energy generation in every common engine for the last 100 years. In engines it goes something like this.

HC + O2 -> (combusts) CO2 + H2O + ? + energy (powers pistons) + {CO + CH4} + [C + hc] + HC

The terms in brackets are the products of partial combustion, gaseous = {} & engine deposit prone =[](CO+C+hc), and non combustion (HC). Note that CO & ? are often toxic gas emmissions, C & hc often end up as engine clogging deposits, & HC is burnt as waste fuel in that catalytic converter or otherwise drips out onto the road. The HC combustion process has always only been partial anyway. Then considering the high & rising fuel $, the fuel $ in food & everything else, the limited reserves of oil which are already causing political tension around the world, & the CO2 which they say is affecting the climate so that we have to pay a C tax as well. Is it really worth it, of course not.

History tells us that the engine that was invented before the petrol engine was in actual fact one that ran on oxyhydrogen as an electrolysis product of water. The orginal authorities chose the petrol one to be developed, and it's been used ever since. That was probably the wrong decision then, and it is much more so today. There was a water car museum in the USA which has been open to the public until recently also. The chemistry of the water engine is outlined as follows.

stored H2O -> (electrolysis on-demand) H2 + O2 + OH (Brown's Gas) -> (combusts) H2O + energy (powers pistons @ 3xHC/gm)

This option is much better than the H2 technology today, because it's safer in that only enough combustible gas is produced for immediate needs (ie. combusable gas is not stored), & also because it produces 300% energy per unit mass of the HC equivalent compared to the 80% for the H2 alone. Oxyhydrogen technology has been used quite extensively in the manufacturing industry of South Korea. How can we use this technology today? Well building another water engine would cost quite alot, but probably no more than its petrol equivalent. For most though today $ is a problem & so is red tape.

However you can simply (diy steps) & affordably (ie. $100s not $1000s or 10000s) convert your engine to hybrid (HC & Oxyhydrogen simultaneous combustion). Upgrading to hybrid will improve engine economy (10-200%[25-100 often]) performance & life. Success includes 1000s of happy readers & upgraders, commercial ventures & TV documentary publicity. Parts & ongoing original organisation assistance become available with the purchase of the technology in the form of e-books. If you would like to pursue the matter further then please visit my profile & see my link, alternatively pose a question, & with my answer I will forward on the link for full explanation & purchase option.

Author: Bruce Thompson

Chemistry and Goals of Chemists

2008-10-23T20:39:00.000-07:00

Chemistry is a science of substances, their properties, and how and why materials combine or separate to form different substances. Atoms, molecules and compounds are the involved ones in the study of Chemistry. In other words, it is how atoms interact to form molecules and how molecules interact with each other. It also looks into the composition of substances and their properties. The outer electron orbits or shells primarily determine the chemical characteristics of a material and whether materials will chemically combine. Thus Chemistry is the study of the composition of matter and the changes that take place in that composition. If we place a bar of iron outside our window, the iron bar will soon begin to rust. If we pour vinegar on baking soda, the mixture fizzes. If we hold a sugar cube over a flame, the sugar begins to turn brown and give off steam. The goal of chemistry is to understand the composition of substances such as iron, vinegar, baking soda, and sugar and to understand what happens during the changes described here.

The term chemistry has grown out of an earlier field of study known as alchemy. Alchemy has been described as a kind of pre-chemistry, in which scholars studied the nature of matter but without the formal scientific approach that modern chemists use. The term alchemy is probably based on the Arabic name for Egypt, al-Kimia, or the "black country." Ancient scholars learned a great deal about matter, usually by trial- and-error methods. For example, the Egyptians mastered many technical procedures such as making different types of metals, manufacturing colored glass, dying cloth, and extracting oils from plants. Alchemists of the Middle Ages discovered a number of elements and compounds and perfected other chemical techniques, such as distillation and crystallization. The modern subject of chemistry did not appear, however, until the eighteenth century. At that point, scholars began to recognize that research on the nature of matter had to be conducted according to certain specific rules. Among these rules was one stating that ideas in chemistry had to be subjected to experimental tests. Nowadays keeping in view the overall significance and versatility of chemistry, we can say that:

Chemistry is a science: There is only one sanctioned procedure for determining whether a statement about matter is really chemistry: the exhaustive, inefficient, but highly successful scientific method. Chemists often arrive at new results by nonscientific means (like luck or sheer creativity), but their work isn't chemistry unless it can be reproduced and verified scientifically.

Chemistry is a systematic study: Chemists have devised several good methods for solving problems and making observations. For example, analytical chemists often use protocols (thoroughly tested recipes) for determining the concentrations of substances in a sample. Chemists use well-defined techniques like spectroscopy and chromatography to study new or unknown substances.

Chemistry is the study of the composition and properties of matter: Chemistry is the study of the composition and properties of matter as it answers questions like, "What kind of stuff is a sample made of? What does the sample look like on a molecular scale? How does the structure of the material determine its properties? How do the properties of the material change when we increase temperature, or pressure, or some other environmental variable?"

Chemistry is the study of the reactivity of substances: Chemistry is the study of the reactivity of substances as one material can be changed into another by a chemical reaction. A complex substance can by made from simpler ones. Chemical compounds can break down into simpler substances. For example, fuels burn, food cooks, leaves turn their colors in the fall, cells grow, medicines cure and it is both their chemistry and the chemistry which is concerned with the essential processes that make these changes happen. Today, the science of chemistry is often divided into four major areas: organic, inorganic, physical, and analytical chemistry. Each discipline investigates a different aspect of the properties and reactions of matter.

Organic chemistry: Organic chemistry is the study of carbon compounds. That definition sometimes puzzles beginning chemistry students because more than 100 chemical elements are known. How does it happen that one large field of chemistry is devoted to the study of only one of those elements and its compounds? The answer to that question is that carbon is a most unusual element. It is the only element whose atoms are able to combine with each other in apparently endless combinations. Many organic compounds consist of dozens, hundreds, or even thousands of carbon atoms joined to each other in a continuous chain. Other organic compounds consist of carbon chains with other carbon chains branching off them. Still other organic compounds consist of carbon atoms arranged in rings, cages, spheres, or other geometric forms. The scope of organic chemistry can be appreciated by knowing that more than 90 percent of all compounds known to science (more than 10 million compounds) are organic compounds. Organic chemistry is of special interest because it deals with many of the compounds that we encounter in our everyday lives: natural and synthetic rubber, vitamins, carbohydrates, proteins, fats and oils, cloth, plastics, paper, and most of the compounds that make up all living organisms, from simple one-cell bacteria to the most complex plants and animals.

Inorganic chemistry: Inorganic chemistry is the study of the chemistry of all the elements in the periodic table except for carbon. Like their cousins in the field of organic chemistry, inorganic chemists have provided the world with countless numbers of useful products, including fertilizers, alloys, ceramics, household cleaning products, building materials, water softening and purification systems, paints and stains, computer chips and other electronic components, and beauty products. The more than 100 elements included in the field of inorganic chemistry have a staggering variety of properties. Some are gases, others are solid, and a few are liquid. Some are so reactive that they have to be stored in special containers, while others are so inert (inactive) that they virtually never react with other elements. Some are so common they can be produced for only a few cents a pound, while others are so rare that they cost hundreds of dollars an ounce. Because of this wide variety of elements and properties, most inorganic chemists concentrate on a single element or family of elements or on certain types of reactions.

Physical chemistry: Physical chemistry is the branch of chemistry that investigates the physical properties of materials and relates these properties to the structure of the substance. Physical chemists study both organic and inorganic compounds and measure such variables as the temperature needed to liquefy a solid, the energy of the light absorbed by a substance, and the heat required to accomplish a chemical transformation. A computer is used to calculate the properties of a material and compare these assumptions to laboratory measurements. Physical chemistry is responsible for the theories and understanding of the physical phenomena utilized in organic and inorganic chemistry.

Analytical chemistry: Analytical chemistry is that field of chemistry concerned with the identification of materials and with the determination of the percentage composition of compounds and mixtures. These two lines of research are known, respectively, as qualitative analysis and quantitative analysis. Two of the oldest techniques used in analytical chemistry are gravimetric and volumetric analysis. Gravimetric analysis refers to the process by which a substance is precipitated (changed to a solid) out of solution and then dried and weighed. Volumetric analysis involves the reaction between two liquids in order to determine the composition of one or both of the liquids.

In the last half of the twentieth century, a number of mechanical systems have been developed for use in analytical research. For example, spectroscopy is the process by which an unknown sample is excited (or energized) by heating or by some other process. The radiation given off by the hot sample can then be analyzed to determine what elements are present. Various forms of spectroscopy are available (X-ray, infrared, and ultraviolet, for example) depending on the form of radiation analyzed. Other analytical techniques now in use include optical and electron microscopy, nuclear magnetic resonance (MRI; used to produce a three-dimensional image), mass spectrometry (used to identify and find out the mass of particles contained in a mixture), and various forms of chromatography (used to identify the components of mixtures).

Other fields of chemistry: The division of chemistry into four major fields is in some ways misleading and inaccurate. In the first place, each of these four fields is so large that no chemist is an authority in any one field. An inorganic chemist might specialize in the chemistry of sulfur, the chemistry of nitrogen, the chemistry of the inert gases, or in even more specialized topics. Secondly, many fields have developed within one of the four major areas, and many other fields cross two or more of the major areas. For an example of specialization, the subject of biochemistry is considered a subspecialty of organic chemistry. It is concerned with organic compounds that occur within living systems. An example of a cross-discipline subject is bioinorganic chemistry. Bioinorganic chemistry is the science dealing with the role of inorganic elements and their compounds (such as iron, copper, and sulfur) in living organisms. At present, chemists explore the boundaries of chemistry and its connections with other sciences, such as biology, environmental science, geology, mathematics, and physics. A chemist today may even have a so-called nontraditional occupation. He or she may be a pharmaceutical salesperson, a technical writer, a science librarian, an investment broker, or a patent lawyer, since discoveries by a traditional chemist may expand and diversify into a variety of fields that encompass our whole society.

Chemists have two major goals. One is to find out the composition of matter in order to learn what elements are present in a given sample and in what percentage and arrangement. This type of research is known as analysis. A second goal is to invent new substances that replicate or are different from those found in nature. This form of research is known as synthesis. In many cases, analysis leads to synthesis. That is, chemists may find that some naturally occurring substance is a good painkiller. That discovery may suggest new avenues of research that will lead to a synthetic (human-made) product similar to the natural product, but with other desirable properties (and usually lower cost). Many of the substances that chemistry has produced for human use have been developed by this process of analysis and synthesis.

Author: Dr.Badruddin Khan

Contributions of Ancient Arabian and Egyptian Scientists on Chemistry

2008-10-23T20:37:00.000-07:00

Contributions of Ancient Arabian and Egyptian Scientists on Chemistry
Md. Wasim Aktar* and M. Paramasivam
Deptt. of Agril. Chemicals, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, Nadia, West Bengal, India.
Abstracts
The modern chemistry is based on the findings and thinking of the people of historical age. If no one knows the base and work of the previous on a subject, he or she could mere develop a new thought or findings. For, a civilization must know its past. Hence, the present work is a small effort to find out the contribution of ancient Arabian and Egyptian scientists in the field of Chemistry. Different scientists of different school of thought, correlating different streams of science being Chemistry as a main subject, are described in the present work.
Chemistry deals with the composition and properties of substances and the changes of composition they undergo. It has been divided into Inorganic and Organic. The conception of this in modern Chemistry came from al-Rãzi’s classification of chemical substances into mineral, vegetable and animal. Inorganic Chemistry, deals with the preparation and properties of the elements, and their compounds, originally arose from the study of minerals and metals, whereas Organic Chemistry, which deals with carbon compounds, developed through the investigation of animal and plant products.
Prior to 1828 it was not possible to synthesize organic substances from their elements and, therefore, it was supposed that there existed fundamental difference between Organic and Inorganic Chemistry. In 1828 F. Wohler synthetically prepared urea, an organic substance; thereby revealing that there was no fundamental difference between these two branches of Chemistry. Since carbon compounds were numerous, their study separately made under Organic Chemistry, and study of elements and non-carbon compounds included in Inorganic Chemistry’. (1)
The earliest discoveries in Inorganic Chemistry were made in metallurgy, Materia Medica, painting, enameling, glazing, glass-making, arts, etc. These arts, and many metals, compounds and alloys were known to the Arabs. Similarly, the discoveries in Organic Chemistry were made in the arts of dyeing, tanning, the manufacture of paper, in the study of fats, both of plant and animal origin, in medicine, etc. Thus Chemistry had its sources in photo techniques, mineralogy, metallurgy, Materia Medica and decorative arts. It is the product of transmutation of baser metals into gold
and philosophical thoughts of practical or theoretical interest. Finally, it is the result of the study of the properties of the substances.
A Greek philosopher, Empedocles, held the view that all the four elements, air, water, earth and fire, were the primal elements, and that the various substances were made by their intermixing. He regarded them to be distinct and unchangeable. Aristotle considered these elements to be changeable i.e., one kind of matter could be changed into another kind. (2)
Jábir ibn Hayyãn (Liatinized as Geber), a great Arabian Chemist of the 8th century A.C., modified the Aristotelian doctrine of the four elements, and presented the so-called sulphur-mercury theory of metals. According to this theory metals differ essentially because of different proportions of sulphur and mercury in them. He also formulated the theory of geologic formation of metals.
Unlike his Greek predecessors, he did not merely speculate, but performed experiments to reach certain conclusions. He recognized and stated the importance of experimentation in Chemistry. He combined the theoretical knowledge of the Greeks and practical knowledge of the craftsmen, and himself made noteworthy advance both in the theory and practice of Chemistry.
Jâbir’s contribution to Chemistry is very great. He gave a scientific description of two principle operations of Chemistry. One of them is calcinations which is employed in the extraction of metals from their ores. The other is reduction which is employed in numerous chemical treatments. He improved upon the methods of evaporation, melting, distillation, sublimation and crystallization. These are the fundamental methods employed for the purification of chemical substances, enabling the chemist to study their properties and uses, and to prepare them. The process of distillation is particularly applied for taking extract of plant material.
In the opinion of Jàbir the cultivation of gold was not the only object of a chemist. The preparation of new chemical substances was also regarded by him as the chief object of Chemistry. We owe to him for the first preparation of such substances as arsenic and antimony from their sulphides, and basic lead carbonate. He also did important work in the preparation of steel, and the refinement of metals. Jàbir also deals with such applications as the use of manganese dioxide in glass-making, varnishes to water-proof cloth and protect iron use of iron pyrites for writing in gold and distillation of vinegar to concentrate acetic acid.
The most important discovery made by Jabir was the preparation of sulphuric acid. The importance of this discovery can be realized by the fact that in this modern age the extent of the industrial progress of a country is mostly judged by the amount of. sulphuric acid consumed in that country. Another important acid prepared by him was nitric acid which he obtained by distilling a mixture of alum (of Yemen) and copper sulphate (of Cyprus). Then by dissolving ammonium chloride into this acid, he prepared aqua regia which, unlike acids, could dissolve gold in it.
Jabir classified chemical substances, on the basis of some distinctive features, into bodies (gold, silver, etc.) and souls (mercury, sulphur, etc.) to make the study of their properties easier.
Jãbir is the author of a large number of books on chemistry and a book on astrolabe. About one hundred chemical works ascribed to him are extant. His fame chiefly rests on his chemical books preserved in Arabic. (3)
We find that the author recognized and stated clearly the importance of experimentation more clearly than any other early chemist. He remarkably sound views on methods of chemical research. It is impossible to reach definite conclusions regarding the extent of his contributions until all the Arabic writings ascribed to him have been properly edited and studied. But on the basis of our present knowledge, Jabir appears to be one of the greatest scientist whose influence can be traced throughout the whole period of the historical development of the Arabian and European chemistry. In the light of these facts it would not be improper to call Jãbir as the father of Chemistry.
Some of the chemical writings to which Jãbir’s name is attached were translated into Latin. The first such version, the Book of the Composition of Alchemy was made by Robert of Chester in 1144. The Kitab al-Sab’in (the book of the seventy) was translated by Gerard of Cremona in the 12th century’. The translation of the Sum of Perfection was made by Richard Russell. One of his books has been translated into French by Berthelot. (4)
Several technical terms have passed from Jãbir’s Arabic writings through Latin into the European languages. Among these are realgar (red sulphide of arsenic), tutia (zinc oxide), alkali, antimony, and alembic for distillation Vessel. The Arabic equivalents for the last three words are alqali, ithmad, and al-’anbiq respectively. (5)
Before Jãbir Ibn Hayyan, the Umayyad prince Khalid Ibn Yazid, who was a philosopher, poet and chemist, encouraged Greek philosophers in Egypt to translate Greek scientific works into Arabic. These were among the earliest translations in Arabic from other languages. He was himself deeply interested in medicine, astrology and chemistry. Many chemical works are ascribed to him. One of them is entitled Firdaus al-Hikmah fi’Ilm al-Kimiya. This work was in verse, and contained 2,315 couplets. (6)
An encyclopaedic scientist, and philosopher, Abu Yusuf Ya’qub al-Kindi considered the art of transformation of one metal into the other as an imposture. A few of ‘his numerous works dealing with many sciences are extant. One of his works is on pharmacy, a branch of applied chemistry. (7)

Chemistry was usually mixed up with mineralogy and geology. The oldest Arabian lapidary which may serve as an important source of chemistry was written by ‘Utärid Ibn Muhammad al-Hãsib who flourished in the ninth century. It deals with the properties of precious stones. (8)
In the same century Jãbir’s work was further advanced by al-Räzi who wrote many chemical treatises, and described a number of chemical instruments. One of his treatises consists of 25 pieces of chemical apparatus. He made investigations on specific gravity. One of his important works is on the art of transformation of baser metals into the noble ones. He applied his chemical knowledge for medical purposes, thus laying the foundation of Iatrochemistry. (9)
Other important chemists of this century were Dhu’l-Nün and al-Jàhiz. The former mostly dealt with the art of transmutation of metals. (10) The latter prepared ammonia from animal offals by dry distillation. (11)
In the tenth century Ibn Wahshiyah wrote on chemistry, His work may help to understand chemical symbolism. Maslamah Ibn Ahmad, an astronomer, mathematician and oculist of this century wrote two chemical works entitled, Rutbat al-Hakim and Ghãyat al-Hakim. The second is well known in the Latin translation made in 1252 by the order of King Alfonso under the title Picatrix. (12)
A Persian pharmacologist Abü Mansür Muwaffaq Ibn ‘Ali al-Harawi who flourished in Herat in the tenth century, was apparently the first to think of compiling a treatise on Materia Medica in Persian. He travelled extensively in Persia and India to obtain necessary information. He wrote, between 968 and 977, a book entitled Kitab al-Abniyah ‘an Haqã’iq al-Adwiyah. It contains Greek, Syrian, Arabian, Persian, and Indian knowledge. It deals with 585 remedies (of which 466 are derived from plants, 75 from minerals, and 44 from animals). He classified them into four groups according to their action, and gave the outline of a general pharmacological theory.
Abu Mansür distinguished between sodium carbonate (natrum) and potassium carbonate (qali). He had some knowledge of arsenious oxide, cupric oxide, silicic acid, antimony and so on. He knew the toxicological effects of copper and lead compounds, the depilatory virtue of quicklime, the composition of plaster of Paris and its surgical use. (13)
The greatest Arabian surgeon, Khalaf Ibn ‘Abbäs al-Zahrãwi (d. 1013) wrote a great medical encyclopaedia, al-Tasrif in 30 sections, which contains interesting methods of preparing drugs by sublimation and distillation, but its most important part is the surgical one. (14)
Abü Rayhan Muhammad al-Birüni (973—1048) took a great interest in the determination of the specific gravity of eighteen precious stones and metals. A voluminous unedited lapidary by al- Biruni is extant in unique manuscript in the Escorial Library. It contains a description of a great number of stones and metals from the natural, commercial, and medical point of view. Moreover, he composed a pharmacology (saydalah).Important information could certainly be obtained from his unedited works, on the origin of Indian and Chinese stones and drugs, which appeared in early Arabic scientific works. (15)
Ibn Sinà wrote a treatise on minerals, which was very important and one of the main sources of geological knowledge, also a source of chemistry in Western Europe until the Renaissance.
As mentioned before, mineralogy stood in close relation to chemistry. Nearly fifty Arabic lapidaries have been named. The best known of them is. the ‘Flowers of Knowledge of Stones’, by Shihàb al-Din al-Tifãshi (died in Cairo in 1154). It gives in 25 chapters extensive information on the subject of the same number of precious stones, their origin, geography, examination, purity, price, application for medicinal and magical purposes, and so on. Except for Pliny and the superior Aristotelian lapidary, he quotes only Arabic authors. (16)

The output of the books on Chemistry was very great after the eleventh century. Thus, there are known books of about forty Arabic and Persian chemists. Ibn Khaldun, (d. 1406) the talented Arabian philosopher of history and the greatest intellect of his century, was a violent opponent of the idea of transmutation of metals by chemical means. (17)
Some chemists thought that one metal can be transformed into another by artificial methods. For such transformation they followed different procedures depending on the character and form of the chemical treatment and the substance chosen for this purpose; the substance being called the ‘Noble Stone’ or ‘Philosopher’s Stone’. This may be excrements, or blood, or hair, or eggs, or anything else. After the substance has been specified, it is treated along certain lines mentioned in their books. The result is an earthen or fluid substance which is called Elixir. These chemists think that if Elixir is added to silver which has been heated in a fire, the silver turns into gold. If added to copper which had been heated in a fire, the copper turns into silver.
The question arises whether the metals are of specific differences, each constituting a distinct species, or whether they differ in certain properties and qualities and constitute different kinds of one and the same species?
Abü Nasr al-Färabi and his followers held the opinion that the difference in metals is caused by certain conditions such as humidity and dryness, softness and hardness, and colours such as yellow, white and black. According to him the metals are different kinds of one and the same species.
On the other hand, Ibn Sina and his followers believed that metals have specific differences and belong to different species, each of which has its own differential and genus, like all other species.
According to Abü Nasr al-Färãbi, it is possible to transform one metal into another, because it is possible to change their conditions.
“Ibn Sinà thought that such transformation was impossible. His assumption is based on the fact that specific differences in metals cannot be changed by artificial means. He believed that since the metals are created by the Creator and Determiner of things, God Almighty, and the mystery of their real character was utterly unknown and could not be perceived, any attempt for transformation would be meaningless”. (18)
Ancient Arabs’ art of transformation of metals was based upon Hellenistic and Iranian traditions, but apparently the main principles and the main operations were already established long before the 12th century. Before this century the Arabs had not only made many experiments, and produced several works on this art, but they had begun to doubt and criticise the most advanced theories concerning it. This proves that the standard of their chemical thinking was advanced.
The 12th and 13th centuries added very little to their knowledge about the transformation of metals, but their research continued in various fields. The main chemical writer of this age was Abu‘l-Qãsim Muhammad al-Iraqi who flourished in the second half of the 13th century. He was an experimenter and a theorist. His works represent the full development of the Arabic doctrine. (19)
The 14th century was an enlightened period when a group of intelligent writers began to reject the idea of transformation of metals by chemical means. One of such person was a historian, Rashid al-Din who described such chemical practice in Mongol Persia and expressed his distrust of such chemists. The large encyclopaedic work Nukhbat al-Dahr of al-Dimashqi contains, in part second, much information on metal, their properties, and influences. (19) As usual in Arabic treatises, chemistry is mixed up with mineralogy and geology. (20)
Even in their purely chemical researches on transformation of metals, the Arab chemists achieved by no means unimportant results. In their efforts to discover Elixir they often discovered new chemical processes, and hit upon the catalytic properties of various substances. The pains, which they took in the search of gold, ultimately resulted in their great contribution to the development of modern chemistry.
The last important chemist of the 14th century was ‘Izz al-Din ‘Ali Ibn al- Jildaki. Some twenty treatises are ascribed to him. The list shows al-Jildaki’s great activity as a chemical writer. A complete study of his vast writings is necessary to know what he actually tried to establish. To some extent, this study was made by Ruska, Stapleton, Holm yard, and their disciples.
One of al-Jildaki’s important books entitled Nihâyat al-Talab fi Sharh al-Muktasab contains many quotations from the earlier works, and some novelties, as the use of nitric acid to extract silver out of the gold-silver alloy. Al- Jildaki remarked that the substances do not react except by definite weights. (21) This is one of the four fundamental laws of modern chemistry.
The ancient chemists applied their chemical knowledge to a large number of industrial arts. Only three such arts are mentioned here, which will enable the readers to estimate the extent of their knowledge of Applied Chemistry.
Paper:
Paper was invented by the Chinese who prepared it from the cocoon of the silkworm. Some specimens of Chinese paper extant date back to the second century A.C. The first manufacture of the paper outside China occurred in Samarqand (757). When Samarqand was captured by Arabs the manufacture of paper spread over the whole Arab world including the Maghrib. (Tunis, Morocco, Algiers).

By the end of the 12th century there were four hundred paper mills in Fasalone. In Spain the main centre of manufacture of paper was Shatiba which remained a ancient Arab city until 1239. Cordova was the centre of the business of paper in Spain.
The Arabs developed this art. They prepared paper not only from silk, but also from cotton, rags and wood.In the middle of the 10th century the paper industry was introduced in Spain. In Khurasan paper was made of linen.
There is an early treatise dealing with paper-making, the Umdat al-Kuttab wa ‘Uddatu dhawi’l-Albãb which is ascribed to the Amir al- Mu’izz’ Ibn Badis, a ruler of the Zayri dynasty (1015—61) in Tunis. The 11th chapter of this treatise, dealing with paper, has been edited, translated and elaborately discussed by the foremost student of Arabic paper, Josef Karabacek. This work explains how to prepare the pulp, make the sheets, wash and clean them, colour, polish and paste them, and give them an antique appearance. No text comparable to this in any other language of so early a date is known.
The preparation of pulp involves a large number of complicated chemical processes, which shows the advancement of the chemical knowledge of the Arabs and Egyptians at that time.
The manufacture of writing-paper in Spain is one of the most beneficial contributions of Arabs to Europe. Without paper the scale on which popular education in Europe developed would have not been possible. The preparation of paper from silk would have been impossible in Europe due to the lack of silk production there. The Arabs method of producing paper from cotton could only be useful for the Europeans. After Spain the art of paper-making was established in Italy (1268—76). France owed its first paper mills to ancient Spain. From these countries the industry spread throughout Europe.
Another type of paper; marbled paper, which was common upon end-papers, paper covers and edges of books, was prepared in the East, and exported to the West. About the preparation of marbled paper Roger Bacon tells us: “The Turks have a pretty art of chamoletting of paper, which is not with us in use. They take diverse oiled colours, and put them severally (in drops) upon water; and stirr the water lightly and then wet their paper (being of some thickness) with it, and the paper will be waved, and veined, like Chamolet or Marble’.
Books bound in the West towards the end of the 16th century are found with end-papers brought from the East, but it was not until about a century later that European binders began to make them themselves. Hand-made marbled papers are now rarely used, but more or less clumsily reproduced imitations still serve various purposes.

There is an Arabic word ‘rizma’ meaning a bundle of merchandise, which had been adopted in almost every Western language with slight variations to mean a bundle of paper (English: ream). This also testifies to the Arabic origin of that business in the West. (22)
Tiles :
The industry of tile-making which involves a large number of complex technical and chemical processes, was highly developed by Arabs. The earliest treatise, a Persian text, dealing with the manufacture of faience, was unique of its kind in world literature until the 16th century. It has been written by ‘Abd Allah Ibn ‘Ali Kàshàni in the 13th century. This book entitled Jawahir al-‘Arã’is Wa Aja’ib al-Nafä’is was written on precious stones and perfumes. It explains the manufacture of Faience, the ingredients (as clay, borax, feldspar, cobalt, lapis lazuli, lead, manganese, tin etc.), their mixtures, the kiln processes and implements, the methods of glazing and decorating. This treatise is similar to the various other treatises on precious stones written in Arabic and Persian. The final chapter deals with the art of enamelled pottery. This account is specially valuable because it is based on actual and traditional practice. The maker of the beautiful lustre ‘mihrab’ (arch) of the tomb of Imam Yahyã (now in the Hermitage, Leningrad), dated 1305 A.C., Yusuf Ibn ‘Ali Ibn Muhammad, was possibly a brother of the author. (23)
Ceramics:
The early history of Arabian and Egyptian ceramics has not so far been written. Many interesting specimens have been discovered in recent years which throw much light on the development of this industry in the Arab world. The centers of this industry were situated in Persia, Mesopotamia, Syria, Egypt and Valencia from where various types spread rapidly throughout the Islamic Caliphate.
Under Arabian influence the potters in these Centers revived old technical processes, developed new ones and began to experiment with decorative and ornamental schemes. The Arabian potters readily absorbed progressive ideas but at
the same time maintained great originality. Two types of pottery were in common use; enamelled and lustered. In enamelled pottery (the glazed earthenware) the Ancient s, from an early period, were expert masters. In lustered pottery also they made great progress. “In this the design is painted in a metallic salt on a glazed surface and fixed by firing in smike in a way that gives it a metallic gleam, which varies in different specimens from a bright copper-red to a greenish- yellow tint, and in some cases throws off brilliant iridescent reflections. (24)
In the last chapter of the Persian text Kitab al-Jawähir’ al-’Ara’is Wa ‘Ajã’ib al-Nafa’is, the author describes the techniques of glazing
with two fires (lustres), leaf building, over glaze decoration fired in a muffle kiln. (i.e.,
separated from the flame, the source of heat being outside), haf’t rang, a Persian term
referring to the seven colours of the planets. There may be a reference to the polychrome over glaze technique, the so called minai ware (another Persian term; mina-wash means lustre; mina coloured). The author indicates differences between the art as practiced in Kashan, Baghdad and Tabriz. In Baghdad and Tabriz other kinds of firewood and potash were used.
In the 15th century the Arabian ceramic art was followed by Italian potters, who obtained much of the mature technical knowledge from Arab sources. This technical knowledge proved to be helpful in the revival of ceramic art during the Renaissance. (25)
REFERENCES :-
1. Encyclopaedia Britannica, chicago, 1951, p.360
2. Ibid., p. 355.
3 Sarton George, Introduction to the History of Science, Washington, 1950, Vol I. p. 532.
4. Wasiti, Hakim Nayyar, Tibb al-’Arab ( ãn Urdu Translation of Arabian Medicine by Edward G. Browne), Lahore, 1954, p. 26.
5. Ibid.
6. Hãji Khalifah, Kashf al-Zunün, Istanbul, 1943. Vol., I, p. 1254.
Al-Zirakli, Khair al-Din, Al-’Alãm vol. II p. 342.
7. Sarton, op. cit., p. 559.
8. Ibid., p. 572. Al-Qifti, op. cit. p. 251.
9. Ibid., p. 271. Sarton, op. cit. p. 609.
10. lbid, p. 592.
11. lbid, p. 597.
12. Ibid., pp. 620, 668.
13. Ibid., p. 678.
14. Ibid., p. 681.
15 Ibid., p. 707.
16. Ibid, vol. II, part II, p. 650.

17. Ibn Khaldun, Muqaddimah, English translation by Frenz Rosenthal, London, 1957, vol. 3, p. 267.
18. Ibid. p. 278
19. Haji. Khalifah, op. cit. p. 1936.
20. Sarton, op. cit vol. III, part I, p. 759.
21. Ibid. Vol. II, Part. II, p. 1045.
22. Sarton, op. cit., Vol. III, Part I, p. 321.
23. Sarton, op. cit vol. III , part I, p. 756.
24 Arnold and Guillaume, op. cit. p. 125.

Author: Md. Wasim Aktar

What is Chemistry and How to Tame It?

2008-10-23T20:35:00.000-07:00

Chemistry is the study of matter and its changes. This includes everything in the universe from a simple hydrogen atom to very large replicating molecules in life processes. Chemistry is involved with the development of medicines that control and cure diseases; food production through specific and safe agricultural chemicals; consumer products such as cleaners, plastics and clothing; new methods of energy production, transfer and storage; new materials for electronic components; and new methods for protection and cleanup of the environment. Chemists are needed to help solve some of society's most difficult technological problems through research, development and teaching.

A major branch of chemistry, known as ‘Inorganic Chemistry’, is generally considered to embrace all substances except hydrocarbons and their derivatives, or all substances that are not compounds of carbon (including some of the small molecules of carbon.) It covers a broad range of subjects, among which are atomic structure, crystallography, chemical bonding, coordination compounds, acid-base reactions, ceramics, and various subdivisions of electrochemistry (electrolysis, battery science, corrosion, semi conduction, etc.). It is important to state that inorganic and organic chemistry often overlap. For example, chemical bonding applies to both disciplines, electrochemistry and acid-base reactions have their organic counterparts, catalysts and coordination compounds may be either organic or inorganic.

Regarding the importance of inorganic chemistry, R.T. Sanderson has written: "All chemistry is the science of atoms, involving an understanding of why they possess certain characteristic qualities and why these qualities dictate the behavior of atoms when they come together. All properties of material substances are the inevitable result of the kind of atoms and the manner in which they are attached and assembled. All chemical change involves a rearrangement of atoms. Inorganic chemistry (is) the only discipline within the chemistry that examines specifically the differences among all the different kinds of atoms".

Another major branch of chemistry is ‘Organic Chemistry’ which embraces all compounds of carbon except such binary compounds as the carbon oxides, the carbides, carbon disulfide, etc.; such ternary compounds as the metallic cyanides, metallic carbonyls, phosgene (COCl2), carbonyl sulfide (COS), etc.; and the metallic carbonates, such as calcium carbonate and sodium carbonate. The total number of organic compounds is indeterminate, but a huge number has been identified and named. Important areas of organic chemistry include polymerization, hydrogenation, Isomerisation, fermentation, photochemistry, and stereochemistry. There is no sharp dividing line between organic and inorganic chemistry, for the two often tend to overlap.

Application of the concepts and laws of physics to chemical phenomena is included under the heading ‘Physical Chemistry’ in order to describe in quantitative (mathematical) terms a vast amount of qualitative (observational) information. A selection of only the most important concepts of physical chemistry would include: the electron wave equation and the quantum mechanical interpretation of atomic and molecular structure, the study of the subatomic fundamental particles of matter, application of thermodynamics to heats of formation of compounds and the heats of chemical reaction, the theory of rate processes and chemical equilibria, orbital theory and chemical bonding, surface chemistry, including catalysis and finely divided particles, the principles of electrochemistry and ionization. Although physical chemistry is closely related to both inorganic and organic chemistry, it is considered a separate discipline.

Analytical Chemistry is the subdivision of chemistry concerned with identification of materials (qualitative analysis) and with determination of the percentage composition of mixtures or the constituents of a pure compound (quantitative analysis). The gravimetric and volumetric (or "wet") methods (precipitation, titration and solvent extraction) are still used for routine work and new titration methods have been introduced e.g. cryoscopic, pressure-metric (for reactions that produce a gaseous product), redox methods, and use of a F-sensitive electrode etc. However, faster and more accurate techniques (collectively called instrumental) have been developed in the recent past. Among these are infrared, ultraviolet, and x-ray spectroscopy where the presence and amount of a metallic element is indicated by lines in it's emission or absorption spectrum; colorimetry by which the percentage of a substance in soluble is determined by the intensity of it's colour; chromatography of various types by which the components of a liquid or gaseous mixture are determined by passing it through a column of porous material or on thin layers of finely divided solids; and separation of mixtures in ion exchange columns and radioactive tracer analysis. Optical and electron microscopy, mass spectrometry, microanalysis, Nuclear Magnetic Resonance (NMR) and Nuclear Quadrupole Resonance (NQR) spectroscopy all fall within the area of analytical chemistry. New and highly sophisticated techniques have been introduced in recent years, in many cases replacing traditional methods.

Originally Biochemistry was a subdivision of chemistry but now an independent science, which includes all aspects of chemistry that apply to living organisms. Thus, photochemistry is directly involved with photosynthesis and physical chemistry with osmosis, two phenomena that underline all plant and animal life. Other important chemical mechanisms that apply directly to living organisms are catalysis, which takes place in biochemical systems by the agency of enzymes; nucleic acid and protein constitution and behavior, which is known to control the mechanism of genetics; colloid chemistry, which deals in part with the nature of cell walls, muscles, collagen, etc; acid-base relations, involved in the pH of body fluids; and such nutritional components as amino acids, fats, carbohydrates, minerals, lipids and vitamins, all of which are essential to life. The chemical organization and reproductive behavior of microorganisms (bacteria and viruses) and a large part of agricultural chemistry are also included in biochemistry. Particularly active areas of biochemistry are nucleic acids, cell surfaces (membranes), enzymology, peptide hormones, molecular biology, and recombinant DNA.

Nuclear Chemistry is the division of chemistry dealing with changes in or transformations of the atomic nucleus. It includes spontaneous and induced radioactivity, the fission or splitting of nuclei, and their fusion, or union; also the properties and behavior of the reaction products and their separation and analysis. The reactions involving nuclei are usually accompanied by large energy changes, far greater than those of chemical reactions; that are carried out in nuclear reactors for electric power production and manufacture of radioactive isotopes for medical use, also (in research work) in cyclotrons.

Stoichiometry is the branch of chemistry and chemical engineering that deals with the quantities of substances that enter into, and are produced by, chemical reactions. Stoichiometry provides the quantitative relationship between reactants and products in a chemical reaction. For example, when methane unites with oxygen in complete combustion, 16g of methane require 64g of oxygen. At the same time 44g of carbon dioxide and 36g of water are formed as reaction productions. Every chemical reaction has its characteristic proportions. The method of obtaining these from chemical formulas, equations, atomic weights and molecular weights, and determination of what and how much is used and produced in chemical processes, is the major concern of Stoichiometry.

Many students treat chemistry as "too difficult to understand and prefer to escape and memorize even on the expense of the realization that by doing so they are bound to harm themselves now and deprive the society of their contribution later. Henceforth they should note that although it is somewhat challenging, any reasonably intelligent and dedicated student can succeed in chemistry. They should also realize that there is no use of wasting both money and time for some thing that is either memorized before examination or forgotten thereafter or some portion of it is dropped under the pretext of selection of important topics for the purpose of preparation for examination. One must not waste his/her valuables (money and time) just for the sake of degree and literacy as both of these are bound to have detrimental consequences not only for the individual concerned but also the society for obvious reasons.

Those of the students who get their confidence shattered whenever they come across chemistry may note Some Tips (given below) from tose who have succeeded in Chemistry

Develop good study habits.
Attend all lectures and labs.
Take all lecture notes and make your own notes after understanding things properly.
Use your lecture notes as a guide to your reading in the textbook. Write your questions down if you don't understand something. Ask your teacher if you don't understand a concept.
Make flash cards of definitions, concepts, reactions, structures, and nomenclature that are in the textbook and are emphasized by your teacher in lecture.
Remember that writing something is equivalent to reading it ten times and notes are records for recollecting the material and not something to be memorized in a capsule form.
Do all the homework problems sincerely and with sincerity.
One of the best ways of learning is to find a study partner or to form a study group and work on problems independently and then together.
Keep yourself up –to- date. If you get behind or get a poor grade in class tests, either you want to drop the class or may be made to drop the class.
Try to see the ‘big picture; of the future instead of being mean and escapist.
Practice applying what you have learned in class to the world around you.
Try to foster your own scientific curiosity and wonder around ‘why things are and how they happen’.
Have a positive attitude.
Realize that science requires more self discipline, but offers more rewards.
Try to be organized and recognized.
Persevere and be determined to succeed.

Author: Dr.Badruddin Khan