Objectives (5 - 7 minutes)

1. Understand the characteristics of oxides: Students should be able to identify the main characteristics of oxides, such as the presence of oxygen and the combination with other elements. They should understand that oxides can be acidic, basic, or neutral, depending on the element with which oxygen combines.

2. Differentiate between acidic, basic, and neutral oxides: Students should be able to distinguish between acidic, basic, and neutral oxides. They should understand that acidic oxides react with water to form acids, basic oxides react with water to form bases, and neutral oxides do not react with water.

3. Identify examples of oxides in everyday life: Students should be able to identify examples of oxides in everyday life, such as iron oxide (found in rust) and carbon oxide (one of the main contributors to the greenhouse effect).

   • Secondary objectives:

     1. Apply knowledge about oxides in practical situations: In addition to identifying examples of oxides, students should be able to apply the acquired knowledge to understand how oxides behave in different situations, such as in the formation of acid rain.

     2. Develop research and teamwork skills: The Flipped Classroom model allows students to be more active in their learning process. Therefore, they should be encouraged to research about oxides before class and to work in teams to solve the challenges proposed during the lesson.

Introduction (10 - 15 minutes)

1. Review of previous content: The teacher starts the lesson by briefly reviewing the concepts of chemical elements and the properties of oxygen. He can ask students questions to assess what they remember from these concepts and to prepare them for the new content.

2. Problem-based situations: The teacher presents two problem-based situations to arouse students' interest and show the importance of the subject:

   • Situation 1: "Why does iron rust when in contact with air and water?" - The teacher can explain that iron reacts with the oxygen in the air to form iron oxide, which is the main component of rust. This is an opportunity to introduce the concept of oxides.

   • Situation 2: "How can the burning of fossil fuels cause acid rain?" - The teacher can explain that when fossil fuels burn, they release nitrogen oxides and sulfur oxides into the atmosphere, which react with oxygen and water in the air to form acids. This situation highlights the importance of understanding how oxides behave.

3. Contextualization: The teacher emphasizes the importance of oxides in everyday life, mentioning that they are present in various materials we use daily, such as iron, aluminum, zinc, among others. Additionally, the teacher can mention that oxides play a fundamental role in the formation of rain, soil, and in the respiration of living beings.

4. Engaging students' attention: The teacher can share some curiosities about oxides to spark students' interest:

   • Curiosity 1: "Did you know that titanium oxide is used in many sunscreens for its ability to reflect ultraviolet light from the sun?"

   • Curiosity 2: "And that aluminum oxide is used as an abrasive in many cleaning and polishing products, including sandpaper?"

By the end of the Introduction, students should be engaged and curious to learn more about oxides.

Development (20 - 25 minutes)

1. Activity 1: Oxides in everyday life (10 - 12 minutes):

   • The teacher divides the class into groups of up to five students and gives each group a list of everyday materials (such as nails, coins, aluminum foil, among others).
   • The challenge is for students to identify the possible oxides present in these materials, noting their observations and hypotheses on paper.

2. Activity 2: Oxides reaction (10 - 12 minutes):

   • Still in their groups, students receive a series of vials containing different oxides (such as iron oxide, carbon oxide, copper oxide, among others) and different substances (such as water, vinegar, baking soda, among others).
   • The challenge now is for students to try to predict which reactions will occur when mixing the oxides with the substances, based on what they have learned about acidic, basic, and neutral oxides.

3. Discussion and conclusions (5 - 7 minutes):

   • After the activities, the teacher gathers the class and starts a discussion about the observations made by the students and the reactions they predicted.
   • The teacher clarifies which reactions actually occurred and why, relating them to the theory of oxides.
   • The goal is for students to realize the practical application of what they have learned and to make connections between theory and practice.

The teacher should circulate around the room during the activities, assisting students and asking questions to stimulate critical thinking. Additionally, it is important for the teacher to promote collaboration among group members, encouraging discussion and the exchange of ideas.

Return (10 - 12 minutes)

1. Group Discussion (4 - 5 minutes):

   • The teacher gathers all students in a circle and asks each group to share their discoveries and conclusions from the activities carried out.
   • Each group should have a maximum of 3 minutes to present. During the presentations, the teacher should encourage participation and respect among students, ensuring that everyone has the opportunity to speak and that their contributions are valued.
   • During the presentations, the teacher should ask questions to encourage students to reflect on what they have learned and to make connections with the theory. For example: "How did you manage to identify the oxides in everyday materials? How does this relate to the concept of oxides we studied?".

2. Connection with Theory (3 - 4 minutes):

   • After all presentations, the teacher should summarize the main discoveries and conclusions of the students, highlighting how they relate to the theory of oxides.
   • The teacher should emphasize the points where students demonstrated a good understanding of the subject and point out any mistakes or misunderstandings that may have arisen.
   • It is important for the teacher to correct any errors delicately, so as not to discourage students. Instead, the teacher should see errors as a learning opportunity and encourage students to reflect on them and try again.

3. Final Reflection (3 - 4 minutes):

   • To conclude the lesson, the teacher proposes that students reflect for one minute on the following questions:
     1. What was the most important concept you learned today?
     2. What questions have not been answered yet?
   • After the minute of reflection, the teacher asks some students to share their answers with the class.
   • The teacher should listen attentively to the students' answers, as they can provide valuable feedback on what the students understood and on what questions have not been answered yet.
   • The teacher can use the students' answers to plan the next lesson, ensuring that the students' doubts and difficulties are addressed.

By the end of the Return, students should have consolidated the knowledge acquired during the lesson and have a clear understanding of what they have learned and what they still need to learn. Additionally, they should feel comfortable asking questions and expressing their doubts and difficulties.

Conclusion (8 - 10 minutes)

1. Lesson Summary (2 - 3 minutes):

   • The teacher starts the Conclusion by briefly summarizing the main points covered during the lesson. He reinforces the definition of oxides, the difference between acidic, basic, and neutral oxides, and the importance of oxides in everyday life.
   • For example, the teacher can remind students about the activity of identifying oxides in everyday materials, highlighting the most relevant examples and discussing the reactions that occurred during the oxide reaction activity.

2. Connection between Theory and Practice (2 - 3 minutes):

   • Next, the teacher explains how the lesson connected theory, practice, and application. He reinforces that the goal of the practical activities was to allow students to apply theoretical knowledge about oxides in a concrete and meaningful way.
   • For example, the teacher can mention that the activity of identifying oxides in everyday materials allowed students to see in practice that oxides are present in various materials we use daily. The oxide reaction activity allowed students to better understand how oxides behave in different situations, reinforcing the concept of acidic, basic, and neutral oxides.

3. Extra Study Materials (2 - 3 minutes):

   • The teacher suggests some extra materials for students who wish to deepen their knowledge on the subject. These materials may include explanatory videos, chemistry websites, extra exercises, among others.
   • For example, the teacher can suggest that students watch a video explaining in more detail the reactions of oxides or that they solve some exercises on the subject to reinforce the content.

4. Importance of the Subject (1 minute):

   • Finally, the teacher reinforces the importance of the subject for daily life and for other areas of knowledge. For example, he can mention that knowledge about oxides is essential to understand natural phenomena, such as the formation of rain and soil, and for various technological applications, such as sun protection and metal cleaning.
   • The teacher concludes the lesson by reminding students that chemistry is present in many aspects of our lives and that understanding these concepts helps us better comprehend the world around us.

By the end of the Conclusion, students should have consolidated their knowledge about oxides, understand the importance of the subject, and be motivated to continue learning about chemistry.