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Ammonia, 1994.
Discovery, characteristics, toxicity, dangers and its use in agriculture & industry.
1,350 words (approx. 5.4 pages), 11 sources, $ 47.95
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From the Paper
" Ammonia
The chemical, ammonia, has broad application in both industry and agriculture. During the last century, considerable quantities of this compound have been produced. Although ammonia itself is not inherently poisonous, severe exposures may cause airway destruction and burns of the skin. Moreover, under certain conditions, ammonia can burn or explode. Given the chemical's widespread occurrence, the management of ammonia merits careful analysis.
It remains a relatively unknown fact that the first synthesis of ammonia ranks as one of the most important discoveries in the history of science. In 1840, Justus von Leibeg concluded that a significant component of plant nutrition was "fixed" nitrogen. At that time, fixed nitrogen was available.."
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Alchemy, 1993.
A look at the origins and development, the impact on the science of chemistry, theories, leaders, techniques, goals and the role of Sir Isaac Newton.
3,375 words (approx. 13.5 pages), 30 sources, $ 119.95
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From the Paper
"The purpose of this research is to examine the origins and development of alchemy, from the earliest stages of its practice and through the transitions it made from being a pseudo-science toward becoming a major foundation of the harder science of chemistry. As appropriate, reference will be made to those features of alchemy that appear to have survived the transition and continued to exercise an influence on the environment of scientific research.
The origins of alchemy can be traced as far back as the Greeks and the Hellenistic period, if the historiography of the scientific community is to be taken as a guide. It seems important to include Aristotle in any understanding of the reach of alchemy for the reason that the residue of philosophical and scientific environment of intellectual discipline attributed to..."
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Arsenic, 1993.
A look at the nature and types of carcinogenic dangers from contaminated water and workplaces.
1,350 words (approx. 5.4 pages), 13 sources, $ 47.95
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From the Paper
"Arsenic: A Human Carcinogen
Arsenic has always had an evil reputation. Its use as a homicidal and suicidal agent is widely known. In addition, more recently, its potential for causing harm in the environment is being realized. Abundant studies establish a relationship between arsenic and certain types of cancer. As a contaminant in drinking water, it poses a significant threat to human health.
The alchemists' symbol for arsenic is a coiled serpent (Levander et al., 1977, p. 1). The chemical is famous for its poisonous attributes. Less well.known, however, is the fact that arsenic has also been used as a therapeutic "tonic." For hundreds of years, patients received arsenic for conditions ranging from acute infections to epilepsy, and asthma (Bickley & Papa, 1989, p. 378). Furthermore, both inorganic and organic..."
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Chemistry, 1992.
An overview of the major concerns of this scientific field including chemical change, classification of matter, laws, gases, atomic mass, formulas, periodic table, ionic compounds, acids and bases.
3,600 words (approx. 14.4 pages), 3 sources, $ 127.95
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From the Paper
"Chemistry is a branch of science that is used to explain and reveal the composition, structure, and properties of substances and to demonstrate the changes that they can undergo. For example, interaction with other materials can cause substances to acquire different properties, such as a change in physical form. Therefore, a large part of chemistry is observation--before, during, and after change takes place. There are three fields of study in chemistry--organic, inorganic, and physical chemistry. Organic chemistry deals with the study of compounds made up from carbon forms, such as those found in living beings. Inorganic chemistry covers compounds not found in plants or animals and therefore classed as inorganic (noncarbon compounds). Physical chemistry addresses the actions of chemistry that are resolved using the laws of physics."
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History of Chemistry, 1991.
An overview from Ancient Greece (nature of matter) to the 20th century (atomic discoveries).
1,575 words (approx. 6.3 pages), 2 sources, $ 55.95
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From the Paper
"The history of chemistry involves a journey from its magical and mythological origin to the highly complex and analytical science that it is today. Chemistry, the science which explains the composition of matter and the changes that different forms of matter undergo, did not gain much momentum until the seventeenth century. Prior to the 1600s, the study of chemistry languished in a pre-scientific period, suffering from some prominent misconceptions and untenable theories. Advances made in the nineteenth and twentieth centuries have brought chemistry to such an advanced state that we are able to examine the composition of material on an atomic, and even a sub-atomic level.
Beginning with the use of fire, humans have observed the transformation of matter. Fire burns wood to produce ash, and meat becomes cooked over flame. These changes, known to..."
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Fire Retardants, 1991.
This paper discusses fire retardants: Chemical formulations, advantages and disadvantages of different types.
1,350 words (approx. 5.4 pages), 4 sources, $ 47.95
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From the Paper
"Fire is a lethal force that can easily escape control. In structures, it often starts in the building's furnishings and then ignites the structure itself. One of the keys to fire control, therefore, is to prevent the fire from spreading throughout a building via its contents, usually by depriving the fire of the fuel it needs to grow. It is this premise of flame suppression that underlies most research into flame retardants.
There are several fire types and "hazard situations": nonflaming/smoldering fires, early or small flaming fires, and fully developed large-scale (called post-flashover) fires. Nonflaming/smoldering fires can start from overheating of vulnerable substances or can be self-sustaining over a long ... "
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Freon, 1991.
This paper discusses Freon: Chemical properties, uses and environmental dangers of this chlorofluorocarbon.
1,575 words (approx. 6.3 pages), 8 sources, $ 55.95
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From the Paper
"Freon is the commonly known trade name used by E.I. du Pont de Nemours and Company to refer to a certain class of chemical compounds known as "refrigerants." Refrigerants are synthetic compounds called chlorofluorocarbons that are used to perform a variety of basic jobs. Chlorofluorocarbons generally are considered very stable, safe compounds; they are colorless, odorless, nontoxic, noncorrosive, and nonflammable. They vaporize at 300 degrees. Unfortunately, however, although they are considered nonreactive (or inert), they are believed to undergo destructive reactions when they reach the upper atmosphere that damage the ozone layer.
To make Freons, carbon tetrachloride (CCl4) or chloroform (CHCl3) is combined with anhydrous hydrogen fluoride (HF) and a suitable catalyst. The Freon results when a chlorine or a ... "
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Synthetic Methods for Enantiomers of Drugs, 2002.
An analysis of the various methods of producing pure enatiomeric drugs.
1,650 words (approx. 6.6 pages), 9 sources, APA, $ 53.95
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Abstract
This paper discusses how ever since the ?Thalidomide? incidence last century there has been an ever-increasing amount of resources injected into optical isomeric research and in attaining pure enantiomeric products. It shows how due to different stereochemical characteristics, different isomers will have different interactions with biological receptors in the body, giving rise to different actions. A resultant undesirable effect is therefore inherently possible upon the consumption of chiral drugs, for that reason it is imperative that the end drug mixture is as entiomerically pure as possible. It describes the 3 basic methodologies for single enantiomers: chirality pool, kinetic resolution and asymmetric synthesis and examines the basis of and the techniques of separating them.
From the Paper
"One way of the use of chirality pool molecules merely requires the maintenance of pre-existing chirality throughout a synthesis, with transformation of other parts of the molecule by formation of new chemical bonds or inter-conversion of functional groups. Otherwise, utilising chirality pool can afford a so-called ?control element? for the creation of new stereogenic centres by ?substrate-directable? reactions. Such reactions may involve complete transfer of chirality from one region to another intra-molecularly.[1]"
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St. Johns Wort, 2002.
A discussion on herbal medicines, in particular, St. Johns Wort as compared to conventional drugs.
1,063 words (approx. 4.3 pages), 5 sources, MLA, $ 37.95
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Abstract
This paper analyzes St. Johns Wort (SJW), a common herbal treatment. It offers an insight into how its constituents affect us neurologically with its primary ingredients of hypericin, hyperflorin and various flavanoids and describes how, although SJW can be used for various treatments, the main condition that it is used for is depression. It provides a comparative study of conventional anti-depressive agents and their relative side effects and shows how the demand for herbal medicines today is rising at exponential rates, with an obvious advantage such as reductions in the number of side effects. It evaluates whether herbal medicines all that they claim to be and if they contain any profound pharmacological constituents or whether they give just a placebo effect.
From the Paper
"Herbal medicines are clearly mixtures of more than one active ingredient and in many instances, we are not sure which or how many constituents are pharmacologically important. Furthermore, in trying to acquire the mechanisms of action of plant extracts is often complicated even if we know the active ingredient because such extracts contain a wide range of pharmacologically active constituents that might work together to contribute to the pharmacological activity. [1] Our understanding is further dinted if the molecular basis of the disease under investigation is not well understood."
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The Role of Thermodynamics in Pharmacy, 2002.
A report into how essential thermodynamics is to pharmaceutical scientists.
3,181 words (approx. 12.7 pages), 5 sources, MLA, $ 92.95
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Abstract
This paper examines how fundamental the principles of thermodynamics are to pharmacy. The paper covers the topics of Gibbs free energy change, heat of formation, partial molar free energy, energy change and entropy, and discusses how all these are important in pharmaceutics in deciding drug delivery and dosage form. The paper presents the reader with a clearer insight into how important the above are, with extensive explanations into the three laws of thermodynamics and how they all help the modern day pharmaceutical scientist. Many of the complicated calculations involved in thermodynamics are exemplified through examples.
From the Paper
"A pharmacist is regarded as a professional scientist. Thus he is expected to know more than ever, is a thorough knowledge of thermodynamics. This discipline forms a rudimentary backbone of most of the material sciences as many other disciplines do ?borrow? heavily from this. 1,3 In studying thermodynamics, it attempts to integrate the factual knowledge of pharmacy and it aids the pharmaceutical scientist to predict the solubility, stability, feasibility, compatibility and biological action of drug products fairly accurately. Processes such as partitioning of solutes between immiscible solvents, the solubility of drugs, micellisation and drug-receptor interaction can all be treated in thermodynamic terms. 1Thermodynamics is concerned with the quantitative relationships between heat and other forms of energy, including mechanical, chemical, electric and radiant energy. 1The main feature to remember in the study of thermodynamics is that it is not possible to know the absolute value of the energy of a system but it is possible to record changes in energy that happen when a system undergoes transformation."
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