Lesson Plan | Technical Methodology | Properties of Organic Compounds: Acidity and Basicity

Objectives

Duration: 10 - 15 minutes

The purpose of this stage is to provide a clear overview of the skills and knowledge that students should develop during the class. By understanding the objectives, students will be able to focus on hands-on and experimental activities, recognizing the importance of such skills in the job market, especially in areas like analytical, pharmaceutical, and environmental chemistry.

Main Objectives

1. Identify organic compounds as acids or bases based on their chemical structures.

2. Classify organic compounds in order of acidity and basicity, using concepts from organic chemistry.

Side Objectives

1. Understand the relationship between molecular structure and acid-base properties.

Introduction

Duration: 10 - 15 minutes

The purpose of this stage is to engage students with the topic, showing the practical relevance and application of acid and base concepts of organic compounds in daily life and in the job market. This will help spark interest and prepare students for the practical activities that will follow.

Contextualization

Organic compounds are found in various products we use daily, such as medications, food, and cleaning products. Understanding the acid-base properties of these compounds is essential for various fields, including the pharmaceutical industry, where acidity or basicity can influence a drug's effectiveness, and environmental chemistry, where acidity can affect water and soil quality. By understanding these properties, we can develop better products and solutions to environmental problems.

Curiosities and Market Connection

Curiosity: Did you know that the acidity of vinegar is due to acetic acid, an organic compound? And that caffeine, found in coffee, is a weak base? Market Connection: In the pharmaceutical market, understanding the acid-base properties of compounds is crucial for the development of effective drugs. In the food industry, controlling acidity is fundamental for food preservation. In environmental chemistry, monitoring the acidity of organic compounds helps protect the environment.

Initial Activity

Provocative Question: Ask the students: 'Why is lemon acidic and soap basic? How does this affect its daily use?' Short Video: Show a 2-3 minute video on how the acidity and basicity of organic compounds influence the manufacturing of medicines and cleaning products.

Development

Duration: 60 - 70 minutes

The purpose of this stage is to allow students to apply the theoretical concepts learned practically, developing experimental and analytical skills that are essential for the job market. Through experimentation and the proposed challenges, students will consolidate their understanding of the acidity and basicity of organic compounds, in addition to learning how to work in teams and communicate their results clearly and objectively.

Covered Topics

1. Definition of acidity and basicity in organic compounds
2. Molecular structure and how it influences acidity or basicity
3. Comparison between different organic compounds in terms of acidity and basicity
4. Practical applications of acidity and basicity in the pharmaceutical, food, and environmental industries

Reflections on the Theme

Encourage students to reflect on how the molecular structure of organic compounds can influence their acid-base properties. Ask: 'How can the presence of different functional groups alter the acidity or basicity of a compound? And how can this be relevant in different real-life contexts, such as in drug formulation or industrial waste treatment?'

Mini Challenge

Laboratory of Acidity and Basicity of Organic Compounds

Students will carry out a practical lab activity to test the acidity and basicity of different organic compounds using pH indicators and other analytical techniques.

Instructions

1. Divide the students into groups of 4 to 5 people.
2. Distribute samples of different organic compounds to each group (e.g., acetic acid, citric acid, caffeine, amines, etc.).
3. Provide pH indicators such as litmus paper, phenolphthalein solution, and bromothymol blue solution.
4. Instruct the students to measure the pH of each sample using the provided indicators.
5. Ask the students to record the results and classify the compounds in order of acidity and basicity.
6. After measuring, each group should present their results to the class, explaining the reasoning behind the acidity or basicity of each tested compound.

Objective: Develop practical skills in pH analytical techniques and promote the understanding of acid-base properties of organic compounds through experimentation.

Duration: 40 - 50 minutes

Evaluation Exercises

1. Classify the following compounds in increasing order of acidity: acetic acid, phenol, ethanol, benzoic acid.
2. Explain why amines tend to be basic.
3. Given the compound CH3COOH (acetic acid) and CH3NH2 (methylamine), which is more acidic? Justify your answer.
4. Describe a practical example where the acidity of an organic compound is crucial for its use in the pharmaceutical or food industry.

Conclusion

Duration: 15 - 20 minutes

The purpose of this stage is to consolidate students' learning, ensuring they comprehend the main concepts discussed during the class and apply this knowledge in practical contexts. By promoting discussion and reflection, students can connect theoretical content to practice, developing a deeper and more meaningful understanding of the topic.

Discussion

Initiate a discussion with the students about how molecular structure directly influences the acid-base properties of organic compounds. Ask: 'How can the presence of different functional groups alter the acidity or basicity of a compound?'. Ask students to share their observations and reflections on the experiments conducted. Promote reflection on the discoveries made during the lab and how these can be applied in real contexts, such as in the pharmaceutical, food, and environmental industries. Encourage students to think of practical examples of the use of these properties in their daily lives.

Summary

Summarize and recap the main content presented during the class, highlighting the definition of acidity and basicity in organic compounds, the influence of molecular structure on these properties, and the classification of compounds in order of acidity and basicity. Reinforce the importance of the practical skills developed in the lab, such as pH measurement and result analysis.

Closing

Explain how the class connected theory, practice, and applications, showing the relevance of the topic for the job market and daily life. Highlight the importance of understanding the acid-base properties of organic compounds, emphasizing their practical applications across various industries. Conclude the class by thanking the students for their participation and reinforcing the relevance of the knowledge acquired.