Contextualization

Mixtures are everywhere around us. From the air we breathe to the food we eat, everything is made up of mixtures of different substances. But what exactly is a mixture? A mixture is a substance made by combining two or more different materials in such a way that no chemical reaction occurs. Each material retains its own properties, and they can be physically separated from each other.

In the world of chemistry, there are two main types of mixtures: homogeneous and heterogeneous mixtures. Homogeneous mixtures, also known as solutions, are mixtures where the different particles are evenly distributed and you cannot see the individual components with the naked eye. Examples of this are salt water and air. Heterogeneous mixtures, on the other hand, are mixtures where the different particles are not evenly distributed and you can see the individual components. Examples of this are oil and water and a salad.

Understanding the different types of mixtures is not just an interesting topic in chemistry, but also a fundamental concept that has real-world applications. For example, in the pharmaceutical industry, understanding the different mixtures used in medication can help ensure its effectiveness. In environmental science, understanding mixtures can help us understand how pollution spreads in air and water. In the kitchen, understanding mixtures can help us create delicious recipes.

To delve deeper into this topic, students can refer to the following resources:

1. Types of Mixtures - Khan Academy
2. Mixtures and Solutions - American Chemical Society
3. Homogeneous and Heterogeneous Mixtures - CK-12 Foundation

Students are encouraged to explore these resources and use them as a base for their understanding of mixtures. This project will give them an opportunity to apply this knowledge in a hands-on activity and develop a deeper understanding of the topic.

Practical Activity

Title: Exploring Mixtures: Creating Homogeneous and Heterogeneous Mixtures

Objective of the Project:

The main objective of this project is to create and identify different types of mixtures. Students will get hands-on experience distinguishing between homogeneous and heterogeneous mixtures by creating their own examples.

Detailed Description of the Project:

This project will be divided into two main activities. In the first activity, students will create a homogeneous mixture (solution) and a heterogeneous mixture using everyday materials. In the second activity, they will create a presentation describing the process and the properties of the mixtures they created.

Necessary Materials:

For the first activity, students will need:

• Salt
• Water
• Two transparent containers (cups or beakers)

For the second activity, students will need:

• A computer with internet access
• A presentation software (e.g., PowerPoint, Google Slides)
• A digital camera or smartphone camera for documentation

Detailed Step-by-Step for Carrying Out the Activity:

Activity 1: Creating Homogeneous and Heterogeneous Mixtures

1. In the first container, pour some water (about half full).
2. Gradually add salt to the water, stirring continuously, until the salt dissolves completely. This is your homogeneous mixture (solution).
3. In the second container, add the same amount of water as the first container.
4. Add a few pinches of salt to the second container, but do not stir. This is your heterogeneous mixture.

Activity 2: Presentation and Documentation

1. As a group, discuss the properties of the two mixtures you created. What do they look like? Can you see the individual components? Can you separate the components easily?
2. Using your digital camera or smartphone camera, take photos of each mixture, making sure to capture their unique properties.
3. Research on the internet or in books about other examples of homogeneous and heterogeneous mixtures. Make notes of your findings.
4. Using your presentation software, create a presentation with the following slides:
   • Slide 1: Title of your project, your names, and the date.
   • Slide 2: Introduction to the project. Briefly explain what mixtures are and why they are important.
   • Slide 3: Theory. Explain the concept of homogeneous and heterogeneous mixtures and provide examples.
   • Slide 4: Activity 1. Describe how you created the mixtures, and present the photos you took.
   • Slide 5: Activity 2. Discuss the properties of the mixtures you created and present your research findings on other examples of mixtures.
   • Slide 6: Conclusion. Summarize what you learned from the project and what you found interesting.
   • Slide 7: Bibliography. List the sources you used for your research.
5. Each group member should contribute to the presentation and be prepared to present it to the class.

Project Deliveries

At the end of the project, each group will submit their presentation and a written document. The written document should follow the structure:

1. Introduction:

• Contextualize the theme of mixtures and its relevance in real-world applications.
• State the objective of the project.

2. Development:

• Detail the theory behind homogeneous and heterogeneous mixtures.
• Describe the two activities in detail, including the methodology used, the results obtained, and the properties of the mixtures created.
• Discuss the research conducted on other examples of mixtures.

3. Conclusion:

• Summarize the main points of the project.
• Discuss the learnings acquired and the conclusions drawn about the project.

4. Bibliography:

• List the sources used for the research.

This project is not only an opportunity to understand the different types of mixtures but also to develop valuable skills such as collaboration, problem-solving, and communication. Good luck and have fun exploring the world of mixtures!