Lesson Plan | Active Learning | Concentration Units: Common Concentration

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 to guide the focus of students and the teacher during the lesson. Here, the lesson plan clearly establishes what students should be able to do by the end of the session, ensuring that all efforts are concentrated on achieving these specific goals. This section serves as a compass to guide practical and theoretical activities, ensuring that in-class time is used effectively to consolidate students' prior knowledge and apply it in challenging contexts.

Main Objectives:

1. Empower students to calculate the common concentration of a chemical solution using the formula that relates the mass of the solute to the volume of the solution.

2. Develop practical application skills of theoretical concentration concepts in problem-solving situations, reinforcing content understanding.

Side Objectives:

1. Encourage collaboration and discussion among students during group problem-solving, promoting an active and participatory learning environment.

Introduction

Duration: (15 - 20 minutes)

The introduction serves to engage students and connect their prior knowledge with the practical application of the topic. The proposed problem situations stimulate students to think critically and apply the concepts of common concentration in real contexts, preparing them for subsequent practical activities. The contextualization, on the other hand, aims to show the relevance of the topic in everyday life and in other subjects, increasing students' interest and motivation.

Problem-Based Situations

1. Imagine you are responsible for preparing a hydrochloric acid solution, HCl, for cleaning laboratory glassware. The recipe calls for a concentration solution of 1.5 mol/L. From a bottle containing 120g of HCl, how would you prepare this solution?

2. In a laboratory, a student needs to prepare 500mL of a potassium permanganate solution, KMnO₄, with a concentration of 0.1 mol/L. He has a stock solution of KMnO₄ at 1 mol/L. How could he prepare this solution according to his needs?

Contextualization

The concentration of solutions is an essential skill in many areas, from medicine to the food industry. For example, in medicine, preparing medication solutions requires precision to ensure that doses are correct and effective. Additionally, in industries like food, product quality often depends on the proper dilution of ingredients. These real-life examples help contextualize the importance of calculating concentrations and how mistakes can have serious consequences.

Development

Duration: (70 - 75 minutes)

The Development stage is designed for students to apply their prior knowledge of common concentration practically and collaboratively. Through playful and contextualized activities, they will explore scenarios that simulate real situations where calculating concentrations is essential. This approach not only reinforces understanding of theoretical content but also develops teamwork skills, critical thinking, and problem-solving.

Activity Suggestions

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

Activity 1 - The Mystery of the Disappeared Potion

> Duration: (60 - 70 minutes)

- Objective: Develop skills in calculating common concentration in a fun and mysterious context, promoting the practical use of chemical formulas.

- Description: In this playful activity, students will become chemical detectives in a magical laboratory. They will receive a scenario where a mysterious potion has disappeared and need to recreate it by calculating the common concentration of the ingredients based on clues and chemical formulas.

- Instructions:

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

• Present the scenario of the potion's disappearance and the clues that lead to the ingredients and their possible concentrations.

• Provide formulas to calculate the common concentration and ask students to apply these formulas to find the correct values.

• Each group must prepare a report detailing how they arrived at the concentrations of the different ingredients and how they reconstructed the potion.

• At the end, each group will present their solution and the process used to the whole class.

Activity 2 - Solution Builders

> Duration: (60 - 70 minutes)

- Objective: Apply the concept of common concentration in practice by preparing solutions and performing calculations in a simulated laboratory environment.

- Description: Students will act as chemical engineers, planning and constructing solutions with different concentrations to meet specific usage requirements. They will apply their knowledge of common concentration to prepare solutions at scale, using laboratory equipment.

- Instructions:

• Organize students into groups of up to 5 members.

• Present each group with different scenarios that require the preparation of solutions with specific concentrations.

• Provide the necessary materials, including stock solutions of different concentrations and measuring equipment.

• Groups must plan and prepare the solutions, calculating their common concentrations.

• At the end, the groups will present their solutions, explaining the preparation process and the calculations performed.

Activity 3 - Chemical Formula: The Superchefs Challenge

> Duration: (60 - 70 minutes)

- Objective: Utilize the concept of common concentration in a practical and fun way, relating it to everyday situations.

- Description: In this interactive activity, students will take on the role of chefs in a culinary reality show. They will need to prepare dishes that require the use of seasonings in specific concentrations, applying their knowledge of common concentration to create the perfect mixtures.

- Instructions:

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

• Present each group with recipe cards that specify the required concentration of each seasoning.

• Each group must use real ingredients, representing different substances and their concentrations, to prepare the recipes.

• Students apply common concentration calculations to ensure that the dishes meet the specifications.

• After preparation, a taster (teacher or another student) will evaluate the solutions from the groups.

Feedback

Duration: (15 - 20 minutes)

This stage aims to consolidate students' learning, allowing them to share and reflect on their experiences and discoveries. The group discussion helps identify gaps in understanding and clarify doubts, in addition to promoting a culture of collaborative learning. It is also an opportunity for the teacher to evaluate the achievement of learning objectives and the effectiveness of the practical activities conducted.

Group Discussion

At the end of the activities, gather all students for a group discussion. Start the discussion with a brief introduction, highlighting the importance of sharing the different methods and solutions found by the groups. Encourage each group to share the challenges faced, the strategies adopted, and what they learned during the activity. Use open-ended questions to stimulate reflection and dialogue between the groups, such as 'What were the biggest challenges your group faced when calculating the concentrations?' or 'Was there any moment when the theory did not directly apply to practice?'

Key Questions

1. How did the calculations of common concentration help solve the problems proposed in the activities?

2. What are the main differences your group observed when applying theory in practical situations like the activities carried out?

3. How was collaboration and teamwork important during the activities?

Conclusion

Duration: (5 - 10 minutes)

The Conclusion stage serves to reinforce learning and ensure that students have a clear and consolidated understanding of the concepts discussed during the lesson. By summarizing key points and explaining how theory applies in practice, this section helps to conclusively end the lesson and prepare students for future applications of the knowledge gained.

Summary

In the conclusion, recap the main points discussed about common concentration, emphasizing the formulas and methods of calculation used. Remind students of the practical activities, such as 'The Mystery of the Disappeared Potion' and 'Solution Builders', highlighting how they applied theoretical concepts in practical and playful scenarios.

Theory Connection

Explain how today's lesson connected theory and practice, highlighting the importance of understanding theoretical concepts to solve practical everyday problems. Mention how the activities were designed to simulate real situations where calculating concentrations is essential, preparing students for future applications in laboratories and in their professional lives.

Closing

Wrap up the lesson by emphasizing the relevance of studying common concentration, explaining how this knowledge is fundamental in various practical areas, such as in medicine, chemical industry, and culinary arts. Highlight how the ability to calculate and prepare solutions accurately is crucial for success in many professions and daily activities.