Lesson Plan | Active Learning | Properties of Organic Compounds: Solubility of Organic Compounds

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 essential to guide both the teacher and the students on the study focuses and the competencies to be developed. At this stage, the teacher must clearly clarify what is expected of the students' learning, allowing them to better direct their prior study efforts and classroom participation. Additionally, this section serves as a starting point for practical activities, helping to establish a solid foundation for understanding the topic at hand.

Main Objectives:

1. Empower students to identify and differentiate organic compounds based on their solubility properties in water and organic compounds.

2. Develop the ability to predict the solubility of organic compounds in different solvents based on molecular structure.

Side Objectives:

1. Encourage collaboration and critical thinking through group discussions during practical activities.

Introduction

Duration: (15 - 20 minutes)

The purpose of the Introduction stage is to engage students and bridge the gap between the theoretical knowledge acquired at home and its practical application in the classroom. The problem-based situations are designed to activate critical thinking and prepare students for practical activities, while the contextualization seeks to show the relevance of studying the solubility of organic compounds in real scenarios, increasing students' interest and motivation.

Problem-Based Situations

1. Imagine you are in a laboratory and need to determine if an unknown compound is soluble in water or in other organic solvents. What factors would influence your decision? Consider that some compounds may be partially soluble in both types of solvent.

2. Think of an industrial scenario where the solubility of different organic compounds in specific solvents is crucial for the production of chemicals. How is solubility tested in industry and what are the practical implications of choosing the wrong solvent?

Contextualization

The solubility of organic compounds is a central theme not only in research laboratories but also in the chemical and pharmaceutical industry. For example, in the pharmaceutical industry, the solubility of an active ingredient can directly affect its efficacy, absorption, and stability. Understanding how different functional groups affect the solubility of compounds is crucial for the development of new medications. Additionally, the solubility of organic pollutants in water is an important topic in environmental management, influencing wastewater treatment and aquifer contamination.

Development

Duration: (70 - 75 minutes)

The Development stage is crucial for students to practically apply the knowledge acquired about the solubility properties of organic compounds. Through the proposed activities, students have the opportunity to work in teams, develop problem-solving skills, and experiment with the scientific method. This segment is designed to be highly interactive and engaging, allowing students to learn by doing and explore the content in a deep and meaningful way.

Activity Suggestions

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

Activity 1 - The Mystery of Solubility

> Duration: (60 - 70 minutes)

- Objective: Identify organic compounds based on their relative solubilities in different solvents.

- Description: In this activity, students will be divided into groups of up to 5 people and will receive vials containing 10 different organic compounds in solid state, each identified only by a code. They must determine the solubility of each compound in water, ethanol, and ethyl ether. The challenge is to identify the compounds based on the solubility results, comparing them with a reference table that includes the physicochemical properties of the compounds.

- Instructions:

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

• Distribute a set of coded vials to each group. Each vial contains a different organic compound.

• Provide each group with three 100 ml beakers, one containing water, one ethanol, and one ethyl ether.

• Instruct students to test the solubility of each compound in each solvent, recording the results in a provided table.

• Students should use the reference table to compare the results and attempt to identify the unknown compounds.

• Each group will prepare a presentation of their methods and results for the class.

Activity 2 - The Great Solubility Show

> Duration: (60 - 70 minutes)

- Objective: Develop skills in experimental planning and critical analysis of solubility data.

- Description: Students, organized in groups, will be tasked with planning and executing a series of solubility tests using common organic compounds. They must select five compounds and test their solubility in a variety of organic and inorganic solvents. After the tests, each group will prepare a report detailing their observations and conclusions.

- Instructions:

• Form groups of up to 5 students and distribute kits of organic compounds and a variety of solvents.

• Each group chooses five compounds to test.

• Students plan and conduct solubility tests, recording the results.

• After the tests, each group writes a report that includes observations, conclusions, and possible practical applications of the results.

• Each group presents their report to the class, highlighting interesting discoveries and challenges faced.

Activity 3 - Cirque du Solubility

> Duration: (60 - 70 minutes)

- Objective: Visualize and understand the molecular interactions that determine the solubility of organic compounds.

- Description: In this playful scenario, each group of students acts as 'juggling chemists', attempting to balance compounds in different solvents to demonstrate their solubility. Using molecular models, students must represent how different molecular structures interact with various solvents and discuss the practical implications of these interactions.

- Instructions:

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

• Distribute molecular models and solvents to each group.

• Each group chooses an organic compound and must set up a 'show' that demonstrates the solubility of the compound in different solvents, using the molecular models.

• The groups present their 'acts' to the class, explaining the observed molecular interactions and their practical implications.

• Conduct a class discussion on the different presentations, focusing on insights gained about the solubility of the compounds.

Feedback

Duration: (15 - 20 minutes)

The purpose of this feedback stage is to consolidate students' learning, allowing them to articulate and reflect on the knowledge acquired during the practical activities. The group discussion helps reinforce understanding of the concepts of solubility of organic compounds and identify any misconceptions or areas of confusion that may persist. Moreover, this stage allows students to develop communication and argumentation skills, which are essential in the field of chemistry and many other areas.

Group Discussion

After completing the practical activities, gather all students for a group discussion. Start by briefly reviewing the objectives of the lesson and ask each group to share the most significant discoveries from their experiences. Encourage them to discuss which factors influenced the solubility of the tested compounds and if there were any surprises in the results. Use this opportunity for students to articulate what they learned and how it applies to real or theoretical situations.

Key Questions

1. Which functional groups were most determinant in the solubility of the tested compounds and why?

2. How does the molecular structure of the compounds influence their solubility in different solvents?

3. Was there any discrepancy between the expected and observed results? How can this be explained?

Conclusion

Duration: (5 - 10 minutes)

The purpose of the Conclusion stage is to consolidate learning by summarizing the key points discussed during the lesson and highlighting the importance and applicability of the covered concepts. This recap helps students to solidify the knowledge acquired and understand how it applies in real and theoretical contexts. Additionally, it reinforces the connection between theory and practice, an essential skill for any science student.

Summary

To conclude, let's recap what was learned about the solubility properties of organic compounds. Students explored different compounds and tested their solubility in various solvents, observing how molecular structure influences these properties. This practical exercise allowed for the direct application of theoretical concepts in a simulated laboratory situation, reinforcing the understanding of solubility.

Theory Connection

Today's lesson was carefully designed to connect theory with practice. Students utilized their prior knowledge about functional groups and molecular structure to predict and explain the experimental results of solubility. This integration allowed for a deeper and more applied understanding of the topic, highlighting the importance of solubility in real and industrial contexts.

Closing

Understanding the solubility properties of organic compounds is crucial not only for academic chemistry but also for various practical applications, such as in the pharmaceutical industry, wastewater treatment, and material production. This knowledge enables chemists and engineers to make informed choices about which solvents to use in different processes, directly affecting the effectiveness and efficiency of those processes.