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The Linear Range of a Calibration Curve

Author: Fábio Augusto; João Carlos de Andrade; Rogério Custodio
March 2000

Abstract
Linear systems are extremely useful in the representation of experimental data and this type of calibration curve is the best known. In these cases, deviations from linearity are usually attributed to chemical and physical effects that were not initially taken into account and complicate the mathematical analysis of the data. The numerical techniques used to [...]


Optimization Methods in Chemistry

Author: Sebastião de Paula Eiras; Aline Renée Coscione; Rogério Custodio; João Carlos de Andrade

Abstract
Methods of optimization have emerged due to the need of improving the performance of several systems that occur in everyday life. Literally, optimization is to make something “as perfect, effective or functional as possible”. Thus, we can define an optimization process as based on instructions for obtaining the best result for a given situation. Scientifically [...]


Supersaturated Solution

Author: Maria Domitila de Menezes; Maria João M. Curto
November 1998

Abstract
The described experiment, focused on students at the high school level, aims to explore physical chemistry concepts by observing the behavior of a supersaturated solution of sodium acetate.
Keywords
solution, supersaturated solution, crystallization, exothermic reaction, teaching.
Authors
Maria Domitila de Menezes
Escola Superior de Educação de Lisboa – Portugal
Maria João M. Curto
INETI – Portugal
Translated by
João C. de Andrade
Revised by
Carol H. [...]


Collapsing Cans

Author: Maria Domitila de Menezes; Maria João M. Curto
November 1998

Abstract
Using an empty beverage can or bottle, this article presents an experiment of easy implementation, to illustrate some Physical Chemistry concepts at the fundamental level.
Keywords
heating, cooling, pressure, physical chemistry, compression, expansion
Authors
Maria Domitila de Menezes
Escola Superior de Educação de Lisboa – Portugal
Maria João M. Curto
INETI – Portugal
Translated by
João C. de Andrade
Revised by
Carol C. Collins
Warning
Attention: “Read [...]