Febrero 2014
REPUBLIC BOLIVARIANA OF VENEZUELA MINISTRY OF P. P. FOR HIGHER EDUCATION POLYTECHNIC UNIVERSITY INSTITUTE "SANTIAGO MARIﾃ前" SCHOOL OF CHEMICAL ENGINEERING (49)
CHEMICAL
Evolution Of The Modern Chemistry Chemical Engineering Glossary Classification Of The Chemistry
Mﾃｩrida
Evolution of the Modern Chemistry The history of chemistry encompasses a span of time reaching from ancient history to the present. By 1000 BC, ancient civilizations used technologies that would eventually form the basis of the various branches of chemistry Chemistry is considered to have become a full-fledged science with the work of Antoine Lavoisier, who developed a law of conservation of mass that demanded careful measurements and quantitative observations of chemical phenomena. The history of chemistry is intertwined with the history of thermodynamics, especially through the work of Willard Gibbs
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Chemical Engineering Glossary Adiabatic - without loss or gain of heat Azeotrope - a specific mixture of components, which at a given pressure cannot be separated by distillation, i.e. the liquid and vapour phases have the same compositions. Bubble Point - upon heating a liquid mixture, this is the point at which bubbles first appear. CSTR - Continuous Stirred Tank Reactor. This may be thought of as a tank to which reactants flow in, and products flow out. In an ideal CSTR the contents of the reactor are uniformly distributed. Dew Point - upon cooling a vapour mixture, this is the point at which droplets of liquid first appear.
Heterogeneous - containing more than one phase. Homogeneous - containing a single phase. Immiscible - Two liquids are said to be immiscible, if when added together they do not mix but form two separate liquid phases. PFR - Plug Flow Reactor. This may be thought of as a long pipe to which the reactants flow in, and the products flow out. In an ideal PFR, the components will be distributed axially, but will have uniform radial distribution.
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Reynold's Number - This is a number which characterises flow. If the Reynold's number is low (under approximately 1800) then the flow is said to be laminar. This may be thought of as the fluid flowing in layers. If the Reynold's number is high (over approximately 2300) then the flow is said to be turbulent. Turbulent flow is considered to be well mixed. Vapour Pressure - Vapour evaporates at the surface of a liquid. The pressure it exerts is known as vapour pressure. The higher the temperature the greater the vapour pressure
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Composition And Branches Of The Chemical The chemical sciences is divided into branches that are: General Chemistry: Study the phenomena common to all matter, its properties and laws. Is divided into: Pure Chemistry: That deals with the study of organic materials and inorganic substances. Is divided into: Organic Chemistry: Study of living matter Inorganic Chemistry: Study lifeless matter
Analytical chemistry: Its purpose is to study material or sample by different methods. Physical Chemistry: Study the phenomena common to these two sciences. Preparative chemistry: Preparation and purification of substances in the laboratory for the development of new products.
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Applied Chemistry: Study procedures pure chemistry to solve problems in different areas. Is divided into: Quimiurgia: Study the application of chemistry in agriculture with a view to its use as raw material in other industries.
Biochemistry: Study the chemical processes that occur in living organisms. Astrochemistry: Studying the existing substantial composition in the universe. It is the science that deals with the chemical composition of the Sun and the planets, stars and diffuse interplanetary or, more generally, interstellar matter. Crystal chemistry: On the relationship between chemical composition and properties and forms of crystallization of substances. Pharmaceutical Chemistry: Study the properties and applications of medicines.
structure,
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Technical or industrial Chemistry deals with the extraction of substances in general or unit operations or particular industry.
Other branches of chemistry: Radiochemistry: Study transformations of elements and radioactive substances. Stoichiometry: The branch of chemistry that is responsible for studying the weight ratios (weight), mass - mass, mole - mole, mass - volume, volume – mol. of the substances involved in a chemical reaction
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Chemical Form A chemical formula is a way to express information about the proportions of atoms that constitute a particular chemical , the use of a single line of chemical element symbols, numbers , and sometimes also other symbols such as parentheses , dashes, parentheses , and ( +) and minus (- ) signs . Chemical formulas are more limiting than the chemical names and structural formulas The simplest types of chemical formulas are called empirical formulas that use only letters and numbers indicating atomic proportional relationships (the numerical proportions of atoms of the same type to the other types). Molecular formulas indicate simple numbers of each type of atom in a molecule of a molecular substance, so are sometimes the same as the empirical formulas (molecules which have only one atom of a particular type), and at other times require greater numbers than do empirical formulas.
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