Contextualization

Chemistry is a science that seeks to understand the composition, structure, properties, and transformations of matter. Within this broad field, we are focusing on a specific topic: mixtures without reaction.

Theoretical Introduction

The notion of mixtures is fundamental in chemistry. A mixture is a combination of two or more pure substances in which each substance maintains its individual properties. They can be divided into two categories: homogeneous and heterogeneous. The distinction between these two groups is based on the uniformity of the mixture. A simple way to think about this is whether you can see the different parts of the mixture (heterogeneous) or if it looks like there is only one substance present (homogeneous).

The second important part of this topic is the idea that there is no chemical reaction occurring between the substances. That is, when the substances are mixed, they do not combine to form new compounds, and none of the original components is transformed in the process.

Importance of the Topic

In the real world, we find examples of mixtures without reaction everywhere and in various contexts. They play an important role in many aspects of our lives, from the food we eat to the products we use daily.

In an industrial context, for example, many production processes involve the combination of ingredients that do not react chemically with each other but together perform the desired function. This can be seen in sectors such as food, cosmetics, beverages, etc.

Understanding this idea of mixtures without reaction is therefore essential not only to understand chemistry but also to understand how many of the products we use daily are made.

Practical Activity: The Great Dissolution

Project Objective

In this project, student groups should deeply understand the concept and types of mixtures without reaction, perform experiments to create and differentiate such mixtures, calculate the concentrations of the solutions, and finally discuss the relevance of this topic in everyday life and in different industry sectors.

Detailed Project Description

Each group should:

1. Research, from reliable sources of different types, about homogeneous and heterogeneous mixtures, differentiating the two.
2. Conduct experiments in the laboratory to create homogeneous and heterogeneous mixtures, and differentiate them based on the observed physical properties.
3. Choose three distinct substances and make mixtures with water, without any chemical reaction occurring between them. Take note of the observations made and the evidence showing that there was no chemical reaction.
4. Calculate the concentrations of the solutions formed, using the masses of the substances and the volume of water used in creating the mixtures.
5. Discuss the relevance and applications of the topic in everyday life and in different sectors.

The experiments should be documented in detail, with photos and notes.

Required Materials

• Scale
• 100mL graduated cylinder
• Three distinct substances
• Water
• Camera (for documentation)
• Various containers (for the mixtures)

Detailed Step-by-Step

1. Research and study about homogeneous and heterogeneous mixtures.
2. Create a detailed script of the experiments to be performed, based on what has been learned so far.
3. In the laboratory, follow the created script, conducting and documenting the experiments.
4. Calculate the concentrations of the solutions formed, using the masses of the substances and the volume of water used in creating the mixtures.
5. Analyze the results obtained, and discuss the relevance and applications of the topic.

Project Deliverables and Connection with Activities

After completing the above steps, each group should submit:

1. A written report detailing the activities carried out. The report should include:
   • Introduction: Contextualization of the topic, the relevance and application in the real world, in addition to the objective of this project.
   • Development: Detailed explanation of the theories studied and the activities carried out in the laboratory, discussion of the results obtained, and the methodology used, including calculations made.
   • Conclusion: Return to the main points, lessons learned, and conclusions drawn from the project.
   • Bibliography: Sources used to support the project.
2. Graphic material (photos and/or videos) documenting the performance of the experiments.

Students should use the written report to fit and complement what was worked on in practice. Additionally, they should also attach the graphic documentation as evidence that they carried out the proposed activities.