Lesson Plan | Active Learning | Solutions: Introduction

Assumptions: This Active Lesson Plan assumes: a 100-minute class, prior student study with both the Book and the start of Project development, and that only one activity (among the three suggested) will be chosen to be conducted during the class, as each activity is designed to take up a significant portion of the available time.

Objectives

Duration: (5 - 10 minutes)

The Objectives stage is crucial for establishing the foundation of knowledge that will be explored during the class. By clearly defining what students should learn, this section helps align expectations and prepare the ground for the practical activities and discussions that will follow. The focus is on ensuring that students can not only recognize the elements of a solution but also apply this knowledge in the analysis and classification of different mixtures in practical activities.

Main Objectives:

1. Identify and differentiate the components of a solution: solute and solvent.

2. Understand and explain why a solution is considered a homogeneous mixture.

Side Objectives:

1. Develop analytical skills to classify mixtures based on the characteristics of homogeneous solutions.

Introduction

Duration: (15 - 20 minutes)

The Introduction stage is designed to engage students through problem situations they have already studied, reinforcing familiarity with the concept of solutions. Furthermore, the contextualization connects the content with real and practical situations, increasing students' interest and understanding of the importance and applicability of solute and solvent concepts in their daily lives.

Problem-Based Situations

1. Imagine you have a glass of water and decide to dissolve a spoonful of sugar in it. After mixing well, the sugar disappears completely, forming a solution. But what really happens at the molecular level? Students should discuss and explain the process of dissolving sugar in water.

2. Think about a bottle of soda. When opened, bubbles form. These bubbles are the result of the release of carbon dioxide that was dissolved in the solution. Students should explore the nature of the dissolved carbon dioxide in soda and discuss how this relates to solutions.

Contextualization

Understanding solutions is fundamental not only in chemistry laboratories but also in many everyday and industrial activities. For example, the process of dissolving salt or sugar in water is a common practice in cooking. Additionally, understanding how gases can be solutes in liquids is essential in the production of carbonated beverages. These practical examples help illustrate the relevance and applicability of the concept of solutions in the real world, making learning more meaningful and interesting for students.

Development

Duration: (70 - 75 minutes)

The Development stage is designed for students to apply and deepen their knowledge about solutions in a practical and interactive way. The suggested activities aim to stimulate scientific investigation, teamwork, and the application of theoretical concepts in practical and everyday contexts. Through this process, students should solidify their understanding of the characteristics and behaviors of solutions, promoting a more meaningful and lasting learning experience.

Activity Suggestions

It is recommended to carry out only one of the suggested activities

Activity 1 - Mixing and Discovering: A Chemical Journey

> Duration: (60 - 70 minutes)

- Objective: Understand how different solutes behave in different solvents and deepen the understanding of homogeneous mixtures.

- Description: Students will be divided into groups and receive different types of solutes (salt, sugar, baking soda) and solvents (water, alcohol, oil). Each group will test the solubility of the solutes in each solvent, recording their observations in a comparative table. After the experiments, each group will present their findings, discussing which combinations resulted in homogeneous mixtures and why.

- Instructions:

• Divide the class into groups of up to 5 students.

• Distribute materials (solute and solvent) to each group.

• Instruct students to test the solubility of the solutes in different solvents.

• Ask them to record their observations on a board in the laboratory.

• Organize a class discussion where each group will present their findings.

• Conduct a reflection on the importance of polarity and other chemical properties in solubility.

Activity 2 - The Case of the Disappearing Solute

> Duration: (60 - 70 minutes)

- Objective: Practice methods of identifying solutes and understand the properties that influence solubility.

- Description: In this activity, students will need to figure out which solute has been dissolved in a series of solutions prepared by the teacher. Each group will receive samples of already prepared solutions, and they will need to use observation methods, such as taste testing (when safe), conductivity testing, and other simple chemical methods to identify the solutes. The goal is to apply theoretical knowledge about the properties of solutes to identify them in unknown solutions.

- Instructions:

• Prepare solutions in advance with different solutes.

• Distribute samples to each group without revealing the solutes.

• Explain and demonstrate how to conduct each testing method.

• Students should record their hypotheses and results for each sample.

• Hold a group discussion to confront hypotheses with the actual solutions.

Activity 3 - Salvation by Solution

> Duration: (60 - 70 minutes)

- Objective: Understand the practical application of solutions and explore the relationship between the properties of the components and the effectiveness of the solution.

- Description: Students will be challenged to create a solution capable of solving a practical problem (for example, a cleaning solution to remove grease stains). They will choose among various available solutes and solvents to formulate the best solution. After formulation, they will test its effectiveness on a surface prepared with stains. This activity emphasizes the practical application of knowledge about solutions and encourages creativity and teamwork.

- Instructions:

• Explain the challenge and present the practical problem to be solved.

• Distribute the available materials to each group.

• Students should briefly research the properties of solutes and solvents.

• Allow groups to test their solutions on the stained surface.

• Each group will present their solution and discuss why they chose certain components.

Feedback

Duration: (10 - 15 minutes)

The purpose of this stage of the lesson plan is to consolidate the learning attained during the practical activities, allowing students to articulate and share their discoveries and understandings. This discussion helps reinforce the concepts of solutions, solubility, and the properties of solutes and solvents, as well as provide a space for reflection on the applicability of these concepts in real contexts. It is an opportunity for students to verbalize their understanding, which aids in the retention of knowledge.

Group Discussion

After completing the practical activities, organize a group discussion with all students. Start by highlighting the importance of sharing experiences and observations. Ask each group how they perceived the interaction between solutes and solvents and what they discovered about the properties affecting solubility. Encourage students to explain how their findings apply in the real world and how this understanding may influence their daily lives or future career decisions.

Key Questions

1. What were the main differences you observed when testing different solutes in different solvents?

2. How did polarity affect the solubility of the solutes you tested?

3. What practical applications can you imagine for the solutions you worked with today?

Conclusion

Duration: (5 - 10 minutes)

The purpose of this stage is to ensure that students consolidate the knowledge acquired, relating theory and practice. The summary allows for a review of key concepts, while the discussion about the everyday applications of solutions helps students realize the importance and ubiquity of these concepts in their lives. This section also serves to reinforce understanding and stimulate ongoing curiosity and interest in the study of Chemistry.

Summary

Summarizes the main concepts addressed about solutions, highlighting the definition of solutions as homogeneous mixtures, and the differentiation between solute and solvent. A review of the observations and results obtained from the practical activities, emphasizing how different solutes interact with different solvents.

Theory Connection

The connection between the theory studied and the practical activities is evidenced by applying concepts of solubility and properties of materials in real experiments. The discussion about polarity and solubility in different solvents illustrates the direct application of theory in practice.

Closing

Highlights the relevance of solutions in everyday life, such as in cooking, cleaning, and industry. Encourages students to recognize the importance of studying solutions in their daily lives and future scientific or technical careers.