Oral presentation about the free topic or STEM (PIA).pptx

Presentacion en ingles sobre atomos

1. Oral presentation about the free topic or STEM project Docente: Norma Cabello Salas Integrantes: CERDA MARTINEZ FATIMA LUCERO GARCIA CORTINEZ YAHEL DAVID MENDOZA DE LA O LAURA ODALIS SALDAÑA ACOSTA FIORELLA ESTEFANIA VARELA GARCIA MAXIMILIANO

2. Introduction . On these occasions, we will talk about the atomic models proposed throughout history as well as the characteristics of each one of them and how each one worked, including its structure.

3. Dalton’s atomic model Postulates. All elements are made up of tiny particles called atoms The atoms of the same element are identical they have the same size mass and chemical properties and therefore are different from those of the other elements. The atoms of an element are not created or destroyed during the chemical reaction but only rearranged. The atoms of an element form compounds.

4. Atomic Model by J. J. Thomson In 1897, Joseph John Thomson performed a series of experiments with cathode rays, in which he subjected these rays to anexternal magnetic field. These experiments showed him that the cathode rays deviated from their trajectory. They also helped himdiscover a new particle. In his proposed model, the atom comprises negatively chargedparticles embedded in a positively charged sphere. The electrically negative particles present in matter were called electrons. He established that the atom is neutral so that the positive charge compensates for the negative charge. He conceived the atom like a compact and indivisible particle

5. Atomic Model Rutherfor The atom has a central nucleus in which the positive charge and practically all the mass are concentrated. The positive charge of the protons is balanced by the negative charge of the electrons, which are outside the nucleus. The nucleus contains, therefore, protons in a number equal to the number of electrons in the atom. The electrons rotate at high speed around the nucleus and are separated from it by a great distance. Rutherford assumed that the atom consisted of a fundamentally empty space, occupied by electrons revolving around a very dense and small central nucleus

6. Atomic Model Bohr's Bohr theory modified the atomic structure model by explaining that electrons move in fixed orbitals (shells) and not anywhere in between and he also explained that each orbit (shell) has a fixed energy.

7. Conclusion . In this topic we learned how each of the atomic models worked as well as a general description of them, also how with the passage of time each idea gave us a new perspective of the same concept as the atomic model is.