Contextualization

The matter surrounding us is diverse and complex, but fundamentally, everything is formed by chemical substances. In a practical view, we can think of two major categories: pure substances and mixtures. Pure substances can be simple, composed of only one type of atom, or compound, formed by more than one type of atom bonded together. Mixtures can be made of pure substances or other mixtures.

The application of these concepts is everywhere, from the food we eat to the medicines we take, from the fuels we use to the cleaning products we have at home. The ability to differentiate and classify substances in our environment helps us to better understand the world and act more consciously and safely.

Studying these concepts is not only to understand how things are made, but to better understand the world around us. It is also an important step for those who want to pursue a career in the exact sciences, such as chemistry, physics, or medicine. However, even if you do not want to follow in this direction, understanding these concepts helps to better understand many current news and events, such as environmental issues, advances in medicine, and technological innovations.

Introduction

The project "Types of Substances and Mixtures" aims to deepen the knowledge on the composition of matter, which is fundamental to the understanding of many natural and technological phenomena. Through practical and theoretical activities, students will be able to understand in a clear and objective way the difference between simple substances, compounds, and mixtures.

Simple substances are those formed by atoms of the same chemical element. The oxygen we breathe and the iron present in automobiles are examples of simple substances. Compound substances, on the other hand, are formed by atoms of different chemical elements. Water, composed of hydrogen and oxygen, and table salt, composed of sodium and chlorine, are examples of compound substances.

Mixtures, in turn, are combinations of two or more substances that do not react chemically or physically with each other. In our daily life, we are always in contact with mixtures. The air we breathe is a mixture of several gases. Sea water is a mixture of water and various dissolved substances, such as salts and gases. The very food we eat is, most of the time, a mixture of various substances.

To study these concepts, we suggest the following resources:

1. Interactive Periodic Table - Fun Science
2. Chemistry: Substances and Mixtures - Khan Academy
3. Substances and Mixtures of Substances - Brasil Escola

Laboratory experiments and demonstrations will also be used to aid in the understanding of these concepts.

Practical Activity

Title of the Activity: Discovering Substances and Mixtures

Project Objectives:

1. Identify and differentiate simple, compound substances, and mixtures.
2. Understand the application and relevance of these concepts in everyday life.
3. Develop research, collaboration, communication, and writing skills.

Detailed Description of the Project:

In this project, groups of students, formed by 3 to 5 members, will carry out a practical activity of collecting, classifying, and analyzing samples of substances and mixtures. After collection and analysis, students must prepare a detailed report explaining their findings, processes, and conclusions.

Materials needed:

1. A sample collection kit, which may include containers, spoons, gloves, pipettes, etc.
2. Magnifying glass or microscope, if available, for more detailed observation.
3. Internet access for research and report preparation.
4. Science books, scientific journals, reference websites, etc., for consultation and references.
5. Word processing software for report preparation.

Detailed step by step for carrying out the activity:

1. Group formation: Students must organize themselves into groups of 3 to 5 members.
2. Sample collection planning: Each group must prepare a plan to collect samples of different substances and mixtures, always considering safety and ethics in collection. Samples can be collected at home, at school, or in the community.
3. Sample collection: Students must collect samples according to their plan. At least three samples of simple substances, three samples of compound substances, and three samples of mixtures should be collected.
4. Sample analysis: Each group must observe their samples, identifying their characteristics and classifying them as simple substances, compound substances, or mixtures. Research can be used to confirm or adjust classifications.
5. Report preparation: Groups must prepare a report that contains the following topics:
   • Introduction: Explanation of the purpose of the project, the concepts involved, and the importance of these concepts in everyday life.
   • Development: Details of the sample collection and analysis process, with descriptions of the samples and justifications for their classifications. Explanation of the concepts of simple substances, compound substances, and mixtures, and how these concepts apply to the collected samples.
   • Conclusions: Reflection on the results, the difficulties faced, the lessons learned, and the possible applications of the concepts studied.
   • Bibliography: List of resources used for research and references.

The activity should be carried out in one week, with an average of two to four hours of work per student.

Project Deliverables:

At the end of the project, each group of students must submit a written report, in digital format, containing all the sections described above. The report must be clear, concise, and well structured. It must contain images of the samples collected and analyzed and references to sources of information used. The quality of the report will be evaluated both in terms of content and writing and organization.

In addition to the report, students should also be prepared to present their findings in an oral presentation in the classroom, if requested by the teacher. This presentation should summarize what was written in the report and clearly show students' understanding of the concepts covered in the project.

With this, it is expected that students acquire the technical skills to identify and differentiate simple substances, compound substances, and mixtures, and socio-emotional skills such as time management, communication, problem solving, creative thinking, and proactivity, among others.