Contextualization

Chemistry is a powerful science. It offers us a special way to explore the world and its phenomena. Of the many topics we address, the study of solutions plays a very important role. Solutions are homogeneous mixtures of two or more substances, one of which is the solute (usually in a smaller quantity) and the other is the solvent (which is in a larger quantity). Understanding solutions and their properties is fundamental to our daily lives.

In this project we will explore a key theoretical concept in the Chemistry of solutions: Mixtures of the same solute. This topic allows us to understand the behavior of solutions when they are mixed, that is, how the concentration of the solute changes. The importance of this could not be more relevant, since the ability to perform this calculation is essential in the daily tasks of a chemistry laboratory, in the pharmaceutical, food, and beverage industries, among others. Therefore, understanding mixtures of the same solute is to understand a little more about the world around us.

Solutions are at the core of our day-to-day lives. When we dissolve a powdered juice envelope in water, we are creating a solution. If we add alcohol to the car's gas tank, again we are dealing with a solution. Understanding how these mixtures behave is fundamental not only for Chemistry, but also for materials science, engineering, medicine, and several other areas. Hence, knowing how to control the concentration of solutions is extremely relevant for many practical and industrial applications.

Practical Activity: "Making a Chemical Cocktail"

Project Objective

The purpose of this project is for students to gain a deeper understanding of mixtures of the same solute through a fun and engaging practical activity. The central concept explored will be the calculation of the initial and final solution concentrations when mixing two or more solutions of the same solute.

Detailed Description of the Project

The students will be divided into groups of 3 to 5 members. Each group will simulate the operation of a fictitious bar and their task will be to create a "chemical cocktail", that is, to mix colored solutions of the same solute but with different concentrations. In addition, the groups will have to calculate the final concentration of the resulting solution and compare it with the expected concentration.

The project should last one week, with an estimated duration of two to four hours per student.

Required Materials

1. Three types of concentrated grape juice (same solute) with different concentrations (available in supermarkets);
2. Water;
3. 200ml transparent cups;
4. Graduated pipettes or syringes;
5. Scale;
6. Paper, pencils and calculator.

Step by Step

Part 1: Preparation

1. Each group should weigh and record the amount of concentrated juice of each type (solute) and the amount of water added (solvent). With this data, calculate and record the concentration of each solution (g/ml).

Part 2: Mixing

2. Next, they should estimate what the final concentration will be by mixing two or more of the prepared solutions, making the necessary calculations.

3. According to the calculations performed, students should mix the solutions and observe the color of the resulting solution.

Part 3: Report

4. Finally, all the data collected and observations made should be recorded in a report.

Project Delivery

The final project report should include:

A Introduction with a contextualization of the topic, its relevance and application in the real world, and the objective of the project.

A Development explaining the concept of mixing the same solute and how it was explored in the project. Detail the methodology used in the practical experiment (preparation and mixing of solutions) and present the results obtained, discussing whether the final solution behaved as expected.

A Conclusion reiterating the most important aspects of the project, what was learned, and what conclusions were reached.

A Bibliography should list the sources used for the project.

By completing this project, students should have acquired technical skills in dealing with mixtures of the same solute, as well socio-emotional skills such as time management, teamwork, critical thinking, and problem solving.