Context

Chemistry is an experimental science based on the study of matter, its properties, how and why substances combine or separate to form other substances, and how substances interact with energy. One of the fundamental concepts that chemistry students must understand is the concept of mixtures and solutions. When we dissolve a solid in a liquid or a gas, the solid is known as the solute, and the liquid or gas is known as the solvent. The final combination of solute and solvent is known as a solution.

A solution can exist in any phase: solid, liquid, or gas. For example, the air we breathe is a gaseous solution, while a soft drink is a liquid solution. In this project, we will focus on liquid solutions, specifically on the mixture of solutions of the same solute and their practical applications.

The ability to work with and understand solutions is extremely important in various areas ranging from medicine to engineering, from cooking to household cleaning. Knowing how to create solutions of different concentrations is fundamental in many professions. For example, pharmacists need to know how to mix solutions to create medications of precise concentrations, while chemists may need to dilute or concentrate a solution for a particular experiment.

In this project, you will have the opportunity to explore this concept more deeply, addressing theoretical and practical aspects, and relating them to real-world situations. Additionally, we hope that this experience contributes to the development of your ability to work in a team, manage time, and solve problems.

To start your journey, we suggest accessing the following resources:

• Khan Academy - Mixtures and Solutions
• Brasil Escola - Chemical Solutions
• Toda Matéria - Homogeneous and Heterogeneous Mixtures

Practical Activity

Activity Title: Laboratory of 'Mixtures of the Same Solute'

Project Objective

In the field of chemistry, it is crucial to learn how to calculate the concentrations of mixtures of solutions of the same solute. The objective of this project is to establish a strong understanding of the calculations and concepts of mixing solutions through practical laboratory activities, research, and report writing.

Detailed Project Description

Groups of 3 to 5 students will have the challenge of creating and documenting a set of laboratory experiments involving the mixture of solutions of the same solute in different concentrations. The project will rely on a combination of research, laboratory activities, and report writing.

Students will have to identify the concept of mole, molarity, solubility, dilution, and percentage concentration, and demonstrate their understanding through precise calculations and theoretical discussions in the reports.

Furthermore, students must solve problems of mixing solutions, calculating final and initial concentrations, and discuss the implications of these mixtures in the real world.

Required Materials

• Selected solute (e.g., sugar, salt, etc.)
• Scale to measure the solute's mass
• Graduated cylinder to measure the volume of water
• Water (as a solvent)
• Glass containers (to prepare the solutions)
• Stirrer (to dissolve the solute in water)
• Pipette (to transfer solutions)

Detailed Step-by-Step for Activity Execution

1. Initial Research and Experiment Planning: Start by researching the mixture of solutions of the same solute. Based on the research, develop a plan for the experiment, including which solutes to use and how to vary the concentrations.

2. Preparation of Solutions: Using the scale, measure the mass of the solute and dissolve it in water to make solutions of different concentrations.

3. Mixing Solutions and Observing Results: Mix the solutions of the same solute in different proportions. Make careful observations and record them.

4. Calculations and Analysis: Calculate the concentration of the mixed solutions and compare them with the original concentrations. Discuss possible errors and their sources.

5. Discussion of Implications: Explore the implications of mixing solutions in real life. For example, their uses in laboratory practices, pharmaceutical and food industries.

6. Report Writing: Write the report including introduction, development, conclusions, and bibliographic references.

Project Deliverables

The deliverables for this project include:

• Research and experiment planning, including a list of materials and detailed process.
• Laboratory notes and observations, including calculations and analysis.
• A discussion of the implications of mixing solutions in the real world.
• A detailed final report including introduction, development, conclusions, and bibliographic references.

The report should reflect the student's understanding of mixing solutions of the same solute, as well as the concepts involved. It should include an explanation of the laboratory procedures and methodology used, as well as the calculations and interpretation of the results obtained. The discussion should connect theory with practice, highlighting the real-world applications of mixing solutions of the same solute and the skills learned during the process.