1 CHEMISTRY AND CHEMISTWithout chemistry our lives would beunrecognisable, for chemistry is at work all aroundus. Think what life would be like without chemistry- there would be no plastics, no electricity and noprotective paints for our homes. There would be no synthetic fibres to clothe us and no fertilisers to help us produce enough food. We wouldn‟t be able to travel because there would be no metal, rubber or fuel for cars, ships and aeroplane. Our lives would be changed considerably without telephones, radio, television or computers, all of which depend on chemistry for the manufacture of their parts. Life expectancy would be much lower, too, as there would be no drugs to fight disease.Chemistry is at the forefront of scientific adventure, and you could make your own contribution to the rapidly expanding technology we are enjoying. Take some of the recent academic research: computer graphics allow us to predict whether small molecules will fit into or react with larger ones - this could lead to a whole new generation of drugs to control disease; chemists are also studying the use of chemicals to trap the sun‟s energy and to purify sea water; they are also investigating the possibility of using new ceramic materials to replace metals which can corrode.Biotechnology is helping us to develop new sources of food and new ways of producing fuel, as well as producing new remedies for the sick. As the computer helps us to predict and interpret results from the test tube, the speed, accuracy and quality of results is rapidly increasing - all to the benefit of product development.It is the job of chemists to provide us with new materials to take us into the next century, and by pursuing the subject, you could make your positive contribution to society.Here are some good reasons for choosing chemistry as a career.Firstly, if you have an interest in the chemical sciences, you can probably imagine taking some responsibility for the development of new technology. New ideas and materials are constantly being used in technology to improve the society in which we live. You could work in a field where research and innovation are of primary importance to standards of living, so you could see the practical results of your work in every day use.Secondly, chemistry offers many career opportunities, whether working in a public service such as a water treatment plant, or high level research and development in industry. Your chemistry-based skills and experience can be used, not only in many different areas within the chemical industry, but also as the basis for a more general career in business.1 As a qualification, chemistry is highly regarded as a sound basis for employment.You should remember that, as the society we live in becomes more technically advanced, the need for suitably qualified chemists will also increase. Although chemistry stands as a subject in its own right, it acts as the bond between physics and biology. Thus, by entering the world of chemistry you will be equipping yourself to play a leading role in the complex world of tomorrow.Chemistry gives you an excellent training for many jobs, both scientific and non-scientific. To be successful in the subject you need to be able to think logically, and be creative, numerate, and analytical. These skills are much sought after in many walks of life, and would enable you to pursue a career in, say, computing and finance, as well as careers which use your chemistry directly.Here is a brief outline of some of the fields chemists work in:Many are employed in the wealth-creating manufacturing industries - not just oil, chemical and mining companies, but also in ceramics, electronics and fibres. Many others are in consumer based industries such as food, paper and brewing; or in service industriessuch as transport, health and water treatment.In manufacturing and service industries, chemists work in Research and Development to improve and develop new products, or in Quality Control, where they make sure that the public receives products of a consistently high standard.Chemists in the public sector deal with matters of public concern such as food preservation, pollution control, defence, and nuclear energy. The National Health Service also needs chemists, as do the teaching profess ion and the Government‟s research and advisory establishments.Nowadays, chemists are also found in such diverse areas as finance, law and politics, retailing, computing and purchasing. Chemists make good managers, and they can put their specialist knowledge to work as consultants or technical authors. Agricultural scientist, conservationist, doctor, geologist, meteorologist, pharmacist, vet ... the list of jobs where a qualification in chemistry is considered essential is endless. So even if you are unsure about what career you want to follow eventually, you can still study chemistry and know that you‟re keeping your options open.What Do Chemistry Graduates Do?Demand for chemists is high, and over the last decade opportunities for chemistry graduates have been increasing. This is a trend that is likely to continue. Chemistry graduates are increasingly sought after to work in pharmaceutical, oil, chemical, engineering, textile and metal companies, but the range of opportunities also spans the food industry, nuclear fuels, glass and ceramics, optical and photographic industries, hospitals and the automotive industry. Many graduates begin in scientific research, development and design, but over the years, about half change, into fields such as sales, quality control, management, or consultancy. Within the commercial world it is recognised that, because of the general training implicit in a chemistry course, chemistry graduates are particularly adaptable and analytical - making them attractive to a very broad spectrum of employers. There has been a growth of opportunity for good chemistry graduates to move into the financial world, particularly in accountancy, retail stores, and computer software houses.（Summarized from: A brief of the Royal Society of Chemistry,1992）2 NOMENCLATURE OF INORGANICCOMPOUNDSNaming elementsThe term element refers to a pure substance with atoms all of a single kind. At present 107 chemical elements are known. For most elements the symbol is simply the abbreviated form of the English name consisting of one or two letters, for example:oxygen = O nitrogen = N magnesium = MgSome elements, which have been known for a long time, have symbols based on their Latin names, for example:iron = Fe (ferrum) copper = Cu (cuprum) lead = Pb (Plumbum)A few elements have symbols based on the Latin name of one of their compounds, the elements themselves having been discovered only in relatively recent times1, for example: sodium = Na (natrium = sodium carbonate)potassium = K (kalium = potassium carbonate)A listing of some common elements may be found in Table 1.Naming Metal Oxides, Bases and SaltsA compound is a combination of positive and negative ions in the proper ratio to give a balanced charge and the name of the compound follows from names of the ions, for example, NaCl, is sodium chloride; Al(OH)3is aluminium hydroxide; FeBr2is iron (II) bromide or ferrous bromide; Ca(OAc)2is calcium acetate; Cr2(SO4)3is chromium (III) sulphate or chromic sulphate, and so on. Table 3 gives some examples of the naming of metal compounds. The name of the negative ion will need to be obtained from Table 2.Negative ions, anions, may be monatomic or polyatomic. All monatomic anions have names ending with -ide. Two polyatomic anions which also have names ending with -ide are the hydroxide ion, OH-, and the cyanide ion, CN-.Many polyatomic anions contain oxygen in addition to another element. The number of oxygen atoms in such oxyanions is denoted by the use of the suffixes -ite and -ate, meaning fewer and more oxygen atoms, respectively. In cases where it is necessary to denote more than two oxyanions of the same element, the prefixes hypo- and per-, meaning still fewer and still more oxygen atoms, respectively, may be used, for example,hypochlorite ClO-Chlorite ClO2-chlorate ClO3-perchlorate ClO4-Naming Nonmetal OxidesThe older system of naming and one still widely used employs Greek prefixes for both the number of oxygen atoms and that of the other element in the compound 2. The prefixes used are (1) mono-, sometimes reduced to mon-, (2) di-, (3) tri-, (4) tetra-, (5) penta-, (6) hexa-, (7) hepta-, (8) octa-, (9) nona- and (10) deca-. Generally the letter a is omitted from the prefix (from tetra on ) when naming a nonmetal oxide and often mono- is omitted from the name altogether.The Stock system is also used with nonmetal oxides. Here the Roman numeral refers to the oxidation state of the element other than oxygen.In either system, the element other than oxygen is named first, the full name being used, followed by oxide 3. Table 4 shows some examples.Naming AcidsAcid names may be obtained directly from a knowledge of Table 2 by changing the name of the acid ion (the negative ion ) in the Table 2 as follows:The Ion in Table 2Corresponding Acid-ate-ic-ite-ous-ide-icExamples are:Acid Ion Acidacetate acetic acidperchlorate perchloric acidbromide hydrobromic acidcyanide hydrocyanic acidThere are a few cases where the name of the acid is changed slightly from that of the acid radical; for example, H2SO4 is sulphuric acid rather than sulphic acid. Similarly, H3PO4 is phosphoric acid rather than phosphic acid.Naming Acid and Basic Salt and Mixed SaltsA salt containing acidic hydrogen is termed an acid salt.A way of naming these salts is to call Na 2HPO4disodiumhydrogen phosphate and NaH2PO4sodium dihydrogenphosphate. Historically, the prefix bi- has been used innaming some acid salts; in industry, for example, NaHCO3 iscalled sodium bicarbonate and Ca(HSO3)2 calcium bisulphite.Bi(OH)2NO3, a basic salt, would be called bismuthdihydroxynitrate. NaKSO4, a mixed salt, would be calledsodium potassium sulphate.3 NOMENCLATURE OF ORGANIC COMPOUNDSA complete discussion of definitive rules of organic nomenclature would require more space than can be allotted in this text. We will survey some of the more common nomenclature rules, both IUPAC and trivial.AlkanesThe names for the first twenty continuous-chain alkanes are listed in Table 1.Alkenes and AlkynesUnbranched hydrocarbons having one double bond are named in the IUPAC system by replacing the ending -ane of the alkane name with -ene. If there are two or more double bonds, the ending is -adiene, -atriene, etc.Unbranched hydrocarbons having one triple bond are named by replacing the ending -ane of the alkane name with -yne. If there are two or more triple bonds, the ending is -adiyne, -atriyne etc. Table 2 shows names for some alkyl groups, alkanes, alkenes and alkynes.The PrefixesIn the IUPAC system, alkyl and aryl substituents and many functional groups are named as prefixes on the parent (for example, iodomethane). Some common functional groups named as prefixes are listed in Table 3.In simple compounds, the prefixes di-, tri-, tetra-, penta-, hexa-, etc. are used to indicate the number of times a substituent is found in the structure: e.g., dimethylamine for(CH3)2NH or dichloromethane for CH2Cl2.In complex structures, the prefixes bis-, tris-, and tetrakis- are used: bis- means two of a kind; tris-, three of a kind; and tetrakis-, four of a kind. [(CH3)2N]2is bis(dimethylamino) and not di(dimethylamino).Nomenclature Priority of Functional GroupsIn naming a compound, the longest chain containing principal functional group is considered the parent. The parent is numbered from the principal functional group to the other end, the direction being chosen to give the lowest numbers to the substituents. The entire name of the structure is then composed of (1) the numbers of the positions of the substituts (and of the principal functional group, if necessary); (2) the names of the substituts;(3) the name of the parent.The various functional groups are ranked in priority as to which receives the suffix name and the lowest position number1.A list of these priorities is given in Table 4.*-CKetonesIn the systematic names for ketones, the -e of the parent alkane name is dropped and -one is added. A prefix number is used if necessary.In a complex structure, a ketone group my be named in IUPAC system with the prefix oxo-. (The prefix keto- is also sometimes encountered.)AlcoholsThe names of alcohols may be: (1) IUPAC; (2) trivial; or, occasionally, (3) conjunctive. IUPAC names are taken from the name of the alkane with the final -e changed to -ol. In the case of polyols, the prefix di-, tri- etc. is placed just before -ol, with the position numbers placed at the start of the name, if possible, such as, 1,4-cyclohexandiol. Names for some alkyl halides, ketones and alcohols are listed in Table 5.EthersEthers are usually named by using the names of attached alkyl or aryl groups followed by the word ether. (These are trivial names.) For example, diethyl ether.In more complex ethers, an alkoxy- prefix may be used. This is the IUPAC preference, such as 3-methoxyhexane. Sometimes the prefix- oxa- is used.AminesAmines are named in two principal ways: with -amine as the ending and with amino- as a prefix. Names for some ethers and amines can be found in Table 6.Carboxylic AcidsThere are four principal types of names for carboxylic acids: (1) IUPAC; (2)trivial;(3)carboxylic acid; and (4)conjunctive. Trivial names are commonly used.AldehydesAldehydes may be named by the IUPAC system or by trivial aldehyde names. In the IUPAC system, the -oic acid ending of the corresponding carboxylic acid is changed to -al, such as hexanal. In trivial names, the -ic or -oic ending is changed to -aldehyde, such as benzaldehyde. Table 7 gives a list of commonly encountered names for carboxylic acids and aldehydes.Esters and Salts of Carboxylic AcidsEsters and salts of carboxylic acids are named as two words in both systematic and trivial names. The first word of the name is the name of the substituent on the oxygen. The second word of the name is derived from the name of the parent carboxylic acid with the ending changed from -ic acid to -ate.AmidesIn both the IUPAC and trivial systems, an amide is named by dropping the -ic or -oic ending of the corresponding acid name and adding -amide, such as hexanamide (IUPAC) and acetamide (trivial).Acid AnhydridesAcid anhydrides are named from the names of the component acid or acids with the word acid dropped and the word anhydride added, such as benzoic anhydride.The names for some esters, amides and anhydrides are shown in Table 8.Acid HalidesAcid halides are named by changing the ending of the carboxylic acid name from -ic acid to -yl plus the name of the halide, such as acetyl chloride.Some names of aryl compounds and aryls are as follows:benzenephenylbenzylarylbenzoic acid4. Introduction to Chemistry Department of FloridaUniversityProgram of StudyThe Department of Chemistry offers programs of study leading to the M.S. and Ph.D. degrees. Students may elect studies in analytical, inorganic, organic, and physical chemistry. Specialty disciplines, such as chemical physics and quantum, bioorganic, polymer, radiation, and nuclear chemistry, are available within the four major areas.The M.S. and Ph.D. degree requirements include a course of study, attendance at and presentation of a series of seminars, and completion and defense of a research topic worthy of publication1. Candidates for the Ph.D. degree must also demonstrate a reading ability of at least one foreign language and show satisfactory performance on a qualifying examination. The M.S. degree is not a prerequisite for the Ph.D. degree. A nonthesisdegree program leading to the M.S.T. degree is offered for teachers.Students are encouraged to begin their research shortly afterselecting a research director, who is the chairman of the supervisory committee that guides the student through a graduate career.Research FacilitiesThe chemistry department occupies 111,000 square feet of space in four buildings: Leigh Hall, the Chemical Research Building, Bryant Hall, and the Nuclear Science Building. Plans for a 65,000-square-foot addition to Leigh Hall are being prepared. A new central science library is located near the chemistry facilities. The University library system holds more than 2.2 million volumes.The major instrumentation includes ultraviolet-visible, infrared, fluorescence, Roman, nuclear magnetic resonance, electron spin resonance, X-ray, ESCA, and mass spectrometers. Many are equipped with temperature-control and Fourier-transform attachments, and some have laser sources. Data-storage and data-acquiring minicomputers are interfaced to some of the instruments, such as the recently constructed quadrupole resonance mass spectrometer. The chemistry department has V AX-11/780 and V AX-11/750 computers as well as multiple terminals connected to IBM machines in the main computer centre on campus.The departmental technical services include two well-equipped stockrooms and glassblowing, electronics, and machine shops to assist in equipment design, fabrication, and maintenance.Financial AidMost graduate students are given financial support in the form of teachingand research assistantships. Stipends range from $9400 - 11,000 for the1986-87 calendar year. State residents and assistantship holders pay in-statefees of about $1400 per calendar year. A limited number of full orsupplemental fellowships are available for superior candidates.Cost of StudyIn 1985-86, in-state students paid a registration fee of $48.62, per credit hour for each semester, out-of-state students paid an additional $ 94.50 ($ 143.12 per credit hour each semester). A small increase in fees is expected for 1986-87.5 ENVIRONMENTAL POLLUTIONWith the coming of the Industrial Revolution the environmentalpollution increased alarmingly. Pollution can be defined as an undesirablechange in the physical, chemical, or biological characteristics of the air, water,or land that can harmfully affect health, survival, or activities of humans orother living organisms. There are four major forms of pollution - waste onland, water pollution (both the sea and inland waters), pollution of the atmosphere and pollution by noise.Land can be polluted by many materials. There are two major types of pollutants: degradable and nondegradable. Examples of degradable pollutantsare DDT and radioactive materials. DDT can decompose slowly buteventually are either broken down completely or reduced to harmless levels. For example, it typically takes about 4 years for DDT in soil to be decomposed to 25 percent of the original level applied. Some radioactive materials that give off harmful radiation, such as iodine-131, decay to harmless pollutants. Others, such as plutonium-239 produced by nuclear power plants, remains at harmful levels for thousands to hundreds of thousands of years.Nondegradable pollutants are not broken down by natural processes. Examples ofnondegradable pollutants are mercury, lead and some of their compounds and some plastics. Nondegradable pollutants must be either prevented from entering the air, water, and soil or kept below harmful levels by removal from the environment.Water pollution is found in many forms. It is contamination of water with city sewage and factory wastes; the runoff of fertiliser and manure from farms and feed lots; sudsy streams; sediment washed from the land as a result of storms, farming, construction and mining; radioactive discharge from nuclear power plants; heated water from power and industrial plants; plastic globules floating in the world‟s oceans; and female sex hormones entering water supplies through the urine of women taking birth control pills.Even though scientists have developed highly sensitive measuringinstruments, determining water quality is very difficult. There are a largenumber of interacting chemicals in water, many of them only in trace amounts.About 30,000 chemicals are now in commercial production, and each yearabout 1,000 new chemicals are added. Sooner or later most chemicals end up in rivers, lakes, and oceans. In addition, different organisms have different ranges of tolerance and threshold levels for various pollutants. To complicate matters even further, while some pollutants are either diluted to harmless levels in water or broken down to harmless forms by decomposers and natural processes, others (such as DDT, some radioactive materials, and some mercury compounds) are biologically concentrated in various organisms1.Air pollution is normally defined as air that contains one or more chemicals in high enough concentrations to harm humans, other animals, vegetation, or materials. There are two major types of air pollutants. A primary air pollutant is a chemical added directly to the air that occurs in a harmful concentration. It can be a natural air component, such as carbon dioxide, that rises above its normal concentration, or something not usually found in the air, such as a lead compound. A secondary air pollutant is a harmful chemical formed in the atmosphere through a chemical reaction among air components.We normally associate air pollution with smokestacks and cars, but volcanoes, forest fires, dust storms, marshes, oceans, and plants also add to the air chemicals we consider pollutants. Since these natural inputs are usually widely dispersed throughout the world, they normally don‟t build up to harmful levels. And when they do, as in the case of volcanic eruptions, they are usually taken care of by natural weather and chemical cycles2.As more people live closer together, and as they use machines to produce leisure, they find that their leisure, and even their working hours, become spoilt by a byproduct of their machines – namely, noise,The technical difficulties to control noise often arise from the subjective-objective nature of the problem. You can define the excessive speed of a motor-car in terms of a pointer reading on a speedometer. But can you define excessive noise in the same way? You find that with any existing simple “noise-meter”, vehicles whichare judged to be equally noisy may show considerable differenceon the meter.Though the ideal cure for noise is to stop it at its source, thismay in many cases be impossible. The next remedy is to absorb iton its way to the ear. It is true that the overwhelming majority ofnoise problems are best resolved by effecting a reduction in thesound pressure level at the receiver. Soft taped music in restaurantstends to mask the clatter of crockery and the conversation at thenext table. Fan noise has been used in telephone booths to mask speech interference from adjacent booths. Usually, the problem is how to reduce the sound pressure level, either at source or on the transmission path.6 ANALYTICAL INSTRUMENT MARKETThe market for analytical instruments is showing a strength only dreamed about as little as five years ago. Driven by the need for greater chemical analysis coming from quality control and government regulation, a robust export market, andnew and increasingly sophisticated techniques, sales are increasingrapidly1.The analytical instrument business' worldwides sales arenearly double their value of five years ago, reaching $ 4.1 billion in1987. Such growth is in stark contrast to the doldrums of severalyears ago when economic recession held back sales growth to littleor nothing. In recent years, the instrumentation market hasrecovered, growing at nearly 9% per year, and it‟s expected t o continue at this rate at least until the 1990. With sales increases exceeding inflation, the industry has seen the real growth demonstrating the important role of chemical instrumentation in areas such as research and development, manufacturing, defense, and the environment in a technologically advancingworld2.Chromatography is the fastest-growing area, comprising 40%, or $ 1.5billion, in 1987 world sales. Chromatographic methods are used extensively inindustrial labs, which purchase about 70% of the devices made, for separation,purification, and analysis. One of the biggest words in all forms of chromatography is “biocompatibility.” Biocompatible instruments are designed to have chemically inert, corrosion-resistant surfaces in contact with the biological samples.Gas Chromatography sales are growing at about the same rate as the instrument market. Some of the newest innovations in GC technology are the production of more instruments with high-efficiency, high-resolution capillaries and supercritical fluid capability.Despite having only a 3% share of the GC market, supercritical fluid chromatography (SFC) has attracted a great deal of attention since its introduction around 1985 and production of the first commercial instrument around 1986. SFC, which operates using asupercritical fluid as the mobile phase, bridgesthe gap between GC and HPLC. The useof these mobile phases allows for higherdiffusion rates and lower viscosities thanliquids, and a greater solvating powerthan gases.Another area showing tremendous growth is ion chromatography (IC). From growth levels of 30% per year in the U.S. and similar levels worldwide, the rate is expected to drop slightly but remain high at 25%. The popularity of IC has been enhanced through extending its applicability from inorganic systems to amino acids and other biological systems by the introduction of biocompatible instruments.Mass spectrometry (MS) sales have been growing about 12% annually. Sales have always been high, especially since MS is the principal detector in a number of hyphenated techniques such as GC-MS, MS-MS, LC-MS, and GC-MS accounts for about 60% of MS sales since it is used widely in drug and environmental testing. Innovations in interface technology such as inductively coupled plasma/MS, SFC/MS, and thermospray or particle beam interfaces for LC-MS have both advanced the technology and expanded the interest in applications. Recent MS instruments with automated sampling and computerized data analysis have added to the attractiveness of the technique for first time users.Spectroscopy accounts for half of all instrument sales and is the largestoverall category of instruments, as the Alpert & Suftcliffe study shows. It can be broken down evenly into optical methods and electromagnetic, or nonoptical, spectroscopies. These categories include many individual high-cost items such as MS, nuclear magnetic resonance spectrometers, X-ray equipment, and electron microscopy and spectroscopy setups. Sales of spectroscopic instruments that are growing at or above the market rate include Fourier transform infrared (FTIR), Raman, plasma emission, and energy dispersive X-ray spectrometers. Others have matured and slowed down in growth, but may still hold a large share of the market.The future of analytical instrumentation does not appear to be without its new stars as there continue to be innovations and developments in existing technology. Among these are the introduction of FT Raman, IR dichroism, IR microscopy, and NMR imaging spectrometers. Hyphenated and automated apparatus are also appearing on the market more frequently. New analytical techniques like capillary electrophoresis, gel capillary electrophoresis, scanning tunneling microscopy for the imaging of conducting systems, atomic force microscopy for the imaging of biological systems, and other techniques for surface and materials analysis are already, or may soon be, appearing as commercialized instruments. And, if the chemical industry continues to do well in the next few years, so too will the sales of analytical instrumentation.The effect of alcohol have both medical and medicolegal implications. The estimationof alcohol in the blood or urine is relevant when the physician needs toknow whether it is responsible for the condition of the patient. From themedicolegal standpoint the alcohol level is relevant in cases of suddendeath, accidents while driving, and in cases when drunkenness is thedefense plea. The various factors in determining the time after ingestion showing maximum concentration and the quality of the alcohol are the weight of the subject, the amount and concentration of the alcohol, how the alcohol was ingested, the presence or absence of food, and the physical state of the subject concerned1.7 DETERMINATION OF BLOOD ALCOHOL WITH GAS CHROMATOGRAPHYThe effects of alcohol vary among individuals and for the same individuals at different times. The action depends mostly on the environment and thetemperament of the individual and on the degree of dilution of the alcoholconsumed. The habitual drinker usually shows relatively less effect than wouldbe seen with an occasional drinker from the same amount of alcohol. Drugspotentiate the effect of alcohol.Many cases document the synergistic effect of alcohol and barbiturates as a cause of death in cases appearing to be suicide. Alcohol itself is probably the most frequent cause of death due to poisoning.A gas-solid chromatographic technique using flame ionization detection and a Porapak Q column has been used for the identification and determination of ethanol, isopropanol, and acetone in pharmaceutical preparations. The technique involves direct injection of an aqueous dilution of the product and thus is simple and direct.Sample Preparation. Two 0.5-ml volumes of an isobutanol internal standard (10 mg/ml water; pipette 12.4 ml of isobutanol and dilute to 1 liter with water) are pipetted into two different 2-dram (7.4-ml) shell vials, one market “known.” and the other “unknown.” A 0.5-ml portion of the ethanol working standard (50 mg/100ml of blood; pipette 5ml of ethanol stock solution; dilute 12.7 ml of absolute ethanol to 1 liter with water, and dilute with 100 m l of blood from blood bank) is transferred to the vial marked “known.” The。
