One of the procedures of the PBL is the generation of questions of study and analysis of the case, since the questions of analysis or discussion around the case are fundamental, because they are those that allow the case to be examined intelligently and in depth, while also leading to the central points of the case. The various modalities adopted today by the PBL are tax on the constructivist theories of learning, which highlight the need for students to inquire or intervene in their environment and build for themselves significant learnings 10. The PBL consists of the approach to a problem situation, where its construction, analysis and/or solution are the central focus of the experience, and where teaching is to deliberately promote the development of the process of researching and resolving the problem in question. The student is also at the heart of this process and working with this method requires non-individual student teamwork 8, 9. PBL is a teaching method that substantially increases the motivation of students, since by its dynamics it makes students active subjects of the learning teaching process 7. The PBL offers students an obvious answer to the questions: Why do we have to learn this information? 6.

PBL is learning that results from the process of entertainment or solving a problem 5. To improve the learning teaching process, various teaching strategies have been designed, including problem-based learning (PBL) 4. The resolution of problems by regressions can be done by traditional methods such as linearized least squares, where it is necessary to perform a summation and propose a system of simultaneous equations, but they can also be summarized with the help of software such as the Stat graphics and Polymath 3. During the resolution of some problems, the resulting mathematical expressions are not feasible to be linearized, for this purpose their resolution is raised by a nonlinear multiple regression. It is usual to resort to the linearization of the resulting models to determine certain parameters, it is feasible to perform simple regressions and even for the resolution of certain problems multiple regressions are proposed as it is in the case of heterogeneous catalysis 2. Because rate is a function of temperature, equations can be combined with these two variables to perform calculations of interest in chemical kinetics, as well as mathematical models serve to predict, explain, and interpret chemical phenomena. The kinetics of a reaction are greatly affected by temperature, and a small variation in temperature can accelerate or slow it down 1. Speed is of interest in kinetic studies as the order of a reaction, as well as other kinetic parameters, can be determined from it. The rate reaction refers to the number of moles of substance transformed per unit volume per unit of time, so speed is an infinitesimal change, and can therefore be expressed as a derivative. Through the PBL cycles generated in the resolution of real problems in chemical kinetics and catalysis, significant learnings are achieved on difficult comprehension topics such as initial rate for the determination of the reaction order, half-life times, temperature effect and heterogeneous catalysis.Р”В¬hemical kinetics is a branch of Physical Chemistry that is responsible for the study of the course of reactions as a function of time, as well as the factors that modify it. The results obtained are compared with traditional methods as multiple linearized least squares, in this way the learning teaching process is strengthened, since the student raises the kinetic model and then solves it with computer tools. This paper is exemplified by the Problem-Based Learning (PBL) scheme and the use of software such as Stat graphics and Polymath to solve the resulting mathematical models. On other side, multiple models can be found with two or more independent variables, however, there are models that are not feasible to linearize and therefore you can make use of nonlinear regression. They conform to linear models, whose parameters such as the ordering to origin and the slope are kinetic parameters, applying linear regression to the experimental data can be obtained linear models that are the simplest to be found.

In the resolution of problems in chemical kinetics and catalysis the mathematical models relate the independent variable that is usually time, with the dependent variable which is normally the concentration of a reactant.

Polymath software multiple reactions