Lesson Plan | Traditional Methodology | Periodic Table: Properties

Objectives

Duration: (10 - 15 minutes)

The purpose of this stage of the lesson plan is to clearly establish what students should learn throughout the lesson. By describing the objectives, the teacher ensures that students know what is expected of them, providing a clear focus for learning and facilitating the understanding of the content covered.

Main Objectives

1. Understand the main properties that can be derived from the periodic table, such as electronegativity.

2. Identify and differentiate the periodic and non-periodic properties of chemical elements.

Introduction

Duration: (10 - 15 minutes)

The purpose of this stage is to capture the students' attention and awaken their interest in the topic of the lesson. By providing historical context and curiosities, the teacher creates a more engaging and meaningful learning environment. This helps students see the relevance of the content in their lives and the world around them.

Context

To begin the lesson, explain to the students that the Periodic Table is one of the most important tools in Chemistry. It organizes all known chemical elements in a way that allows us to predict their properties and behaviors. The Periodic Table is fundamental for both scientists and students, as it facilitates the understanding of the characteristics of the elements and their chemical reactions. Start by highlighting the importance of understanding how the Periodic Table works and what it can tell us about the elements that make up our world.

Curiosities

Did you know that the Periodic Table, as we know it today, was developed by the Russian chemist Dmitri Mendeleev in 1869? He organized the elements based on their chemical and physical properties and even left blank spaces for elements that had not yet been discovered at the time. This shows the incredible vision that Mendeleev had about science and how the Periodic Table has evolved to become an essential tool in modern Chemistry.

Development

Duration: (40 - 50 minutes)

The purpose of this stage is to provide students with a detailed understanding of the periodic and non-periodic properties of the Periodic Table. By explaining each topic clearly and providing examples, the teacher helps students recognize important patterns and trends, facilitating the application of these concepts in different contexts. The proposed questions allow students to practice and reinforce the knowledge acquired during the explanation.

Covered Topics

1. 1. Structure of the Periodic Table: 2. The Periodic Table is organized into periods and groups. Periods are the horizontal rows and indicate the energy level of the electrons. Groups are the vertical columns and indicate the number of electrons in the valence shell. Elements in the same group generally have similar chemical properties. 3. 2. Periodic Properties: 4. Periodic properties are those that vary predictably across the Periodic Table. The main periodic properties include: 5. Electronegativity: The tendency of an atom to attract electrons in a chemical bond. It increases across a period (from left to right) and decreases down a group (from top to bottom). 6. Atomic Radius: The distance between the nucleus of the atom and the valence shell. It decreases across a period and increases down a group. 7. Ionization Energy: The energy required to remove an electron from an atom. It increases across a period and decreases down a group. 8. 3. Non-Periodic Properties: 9. Non-periodic properties do not follow a clear pattern in the Periodic Table. Examples include: 10. Heat of Vaporization: The amount of heat needed to vaporize a substance. 11. Density: The mass per unit volume of a substance. 12. 4. Practical Applications: 13. Explain how knowledge of periodic and non-periodic properties is essential in various fields of science and industry. For example, in the manufacturing of semiconductors, in medicine for the development of new drugs, and in materials engineering to create metal alloys with specific properties.

Classroom Questions

1. 1. Explain how electronegativity varies across a period and down a group in the Periodic Table. 2. 2. Describe the relationship between atomic radius and ionization energy in a group of the Periodic Table. 3. 3. Give examples of two non-periodic properties and explain why they do not follow a clear pattern in the Periodic Table.

Questions Discussion

Duration: (25 - 30 minutes)

The purpose of this stage of the lesson plan is to review and consolidate the knowledge acquired by the students during the lesson. By discussing the answers to the questions presented in the Development stage and engaging students with reflective questions, the teacher reinforces key concepts and promotes a deeper understanding of the content. This feedback moment also provides an opportunity to clarify doubts and ensure that all students have understood well the periodic and non-periodic properties of the Periodic Table.

Discussion

• Discussion of the Questions:

• 1. Explain how electronegativity varies across a period and down a group in the Periodic Table.
• • Electronegativity increases across a period, from left to right, due to the increase in effective nuclear charge, which more strongly attracts the electrons in the valence shell. In a group, electronegativity decreases from top to bottom, as the valence electrons are farther from the nucleus and, therefore, less attracted to it due to the shielding effect of the inner electrons.
• 2. Describe the relationship between atomic radius and ionization energy in a group of the Periodic Table.
• • Atomic radius increases from top to bottom in a group because there is an increase in the number of electron shells. Ionization energy decreases from top to bottom in a group because the valence electrons are farther from the nucleus and are more easily removed due to the lesser attraction effect of the nucleus.
• 3. Give examples of two non-periodic properties and explain why they do not follow a clear pattern in the Periodic Table.
• • Properties like heat of vaporization and density do not follow a clear pattern in the Periodic Table because they depend on many variable factors, such as crystal structure and the nature of intermolecular forces, which are not directly related to the periodic organization of the elements.

Student Engagement

1. Questions and Reflections to Engage Students: 2. 1. Why is it important to understand the variation of electronegativity across the Periodic Table? 3. 2. How can understanding ionization energy be applied in the electronics industry? 4. 3. Discuss in groups how periodic properties influence the chemical behavior of known elements. 5. 4. What other properties of the elements could be considered periodic or non-periodic? Justify your answers. 6. 5. How can knowledge of periodic and non-periodic properties help in predicting the behavior of yet-to-be-discovered elements?

Conclusion

Duration: (10 - 15 minutes)

The purpose of this stage of the lesson plan is to summarize and consolidate the content presented, reinforcing the main points discussed during the lesson. This ensures that students have a clear and organized view of what has been learned, facilitating knowledge retention and future application of the concepts.

Summary

• The Periodic Table organizes chemical elements in periods (horizontal rows) and groups (vertical columns) based on their properties.
• Periodic properties, such as electronegativity, atomic radius, and ionization energy, vary predictably across the Periodic Table.
• Non-periodic properties, such as heat of vaporization and density, do not follow a clear pattern in the Periodic Table.
• Knowledge of periodic and non-periodic properties is essential for various practical applications in fields such as semiconductor manufacturing, medicine, and materials engineering.

The lesson connected theory with practice by explaining how the periodic and non-periodic properties of chemical elements can be used to understand and predict the behavior of elements in different contexts, such as in industry and scientific research. Practical examples were provided to illustrate the application of these concepts in the real world.

The subject presented is of great importance for students' daily lives, as the Periodic Table is an essential tool in Chemistry that facilitates the understanding of the properties and reactions of elements. Furthermore, knowledge of periodic and non-periodic properties helps to predict the behavior of new materials and substances, highlighting its relevance in technological and scientific innovations.