Contextualization

Theoretical Introduction

Chemistry is a central science that permeates various aspects of our daily lives. Within this universe, understanding atomic structure and how atoms combine to form ions is a vital step.

An atom is the smallest unit of a chemical element that maintains its properties. It is composed of three main subatomic particles: protons, neutrons, and electrons. Protons and neutrons are located in the atom's nucleus, while electrons orbit around this nucleus in defined energy areas called energy levels.

An ion, on the other hand, is an atom or molecule that does not have a balance of protons and electrons, resulting in an electric charge. Ions can be positive (cations) if they have more protons than electrons, or negative (anions) if they have more electrons than protons. These characteristics provide chemical reactivity, leading to the formation of ionic compounds with specific properties.

Contextualization

Atoms and ions are present in almost all processes we know. When we prepare lemon juice, for example, the sour taste is due to the presence of hydrogen ions (H+). When brushing our teeth, we use fluoride to strengthen dental enamel, which occurs through the formation of fluoride ions.

In the technological field, the understanding of atoms and ions has allowed the development of battery technology used in cell phones, electric cars, and medical equipment. Furthermore, in the field of medicine, radioisotopes are used to treat certain types of cancer, a process that involves understanding atomic structure and ion formation.

The concepts of atoms and ions are truly fundamental to understanding the world around us and how it functions.

Practical Activity

Activity Title: "Ions in Action!"

Project Objective

The objective of this project is to observe and analyze the formation of positive and negative ions, as well as study their properties and how they interact with each other. Students will conduct a series of experiments, record their observations, and perform analyses to develop a deeper understanding of atomic structure and ions.

Detailed Project Description

This project will be carried out by groups of 3 to 5 students and will last approximately two weeks. During this period, each group will be responsible for planning and executing a series of experiments to investigate the formation and properties of positive and negative ions. These experiments will be conducted using common materials readily available in the school laboratory.

Required Materials

1. Solutions of sodium chloride (NaCl), copper sulfate (CuSO4), sodium hydroxide (NaOH), and hydrochloric acid (HCl).
2. Electrodes - copper and zinc strips.
3. 9-volt battery.
4. Conductive wires.
5. Glass or transparent plastic cups.
6. Litmus paper (pH).

Detailed Step-by-Step Activity Execution

1. Planning: Each group must plan a series of experiments to investigate the formation and properties of positive and negative ions. The plan should include a detailed description of each experiment, an explanation of how the results will be recorded and analyzed, and a list of necessary materials.

2. Execution: The groups will carry out the experiments according to the plan. It is essential to carefully document the procedures, observations, and results of each experiment.

3. Analysis: Based on the experiment results, the groups must conduct a detailed analysis to understand the formation and properties of ions.

4. Discussion: Each group will present their results and analyses to the class, discussing their findings and answering questions from other groups and the teacher.

5. Documentation: Finally, each group must produce a detailed report on the project. This report should include an introduction to the concepts of atoms and ions, a detailed description of the experiments conducted and the results obtained, an analysis of the results, and a conclusion.

Project Deliverables

Upon completion of the experiments, the groups must submit a written report that includes:

• Introduction: Students should introduce the concepts of atoms and ions, explaining their relevance and real-life applications. The project's objective and methodology used should also be mentioned.

• Development: In this section, the groups should describe the experiments they conducted in detail. They should explain each step, record their observations, and present their results. The methodology used and the reasoning behind each experiment should be clearly explained.

• Analysis: The analysis of the results obtained should be done in this section. The groups should interpret their data, explain their findings, and discuss any anomalies or unexpected results. They should make connections with the theoretical concept of atoms and ions and what they observed during the experiments.

• Conclusion: In this section, students should summarize the main points of the work, explaining what they learned from the project and how their findings contributed to the understanding of atoms and ions.

• Bibliography: The groups should list the sources consulted to assist in the project's development, whether for planning the experiments or for understanding the theoretical concepts of atoms and ions.