Contextualization

Chemical formulas represent the composition of chemical compounds. All matter is made up of atoms of different elements, and it is the way these atoms combine that defines the chemical properties of the substance. Although it may seem like an abstract concept, chemical formulas are crucial for understanding our daily life and the world around us.

Chemical formulas are present everywhere, from the ingredients in our food to the composition of the air we breathe. For example, the water we drink is composed of two hydrogen atoms and one oxygen atom, represented by the chemical formula H2O. Every time you see the ingredients on a product label, you are looking at chemical formulas.

They are essential in various fields, such as medicine, engineering, and astronomy. In medicine, for example, medications are carefully designed chemical compounds to interact in specific ways with our bodies. In engineering, chemical formulas are used to create materials with desired properties, such as steel or plastic. In astronomy, scientists use chemical formulas to study the composition of distant stars and planets.

Introduction

In this project, we will explore the different ways to represent a chemical formula, which are the empirical formula, molecular formula, and structural formula. The empirical formula is the simplest way to express the ratio of atoms in a substance, without taking into account the actual structure of the molecule. The molecular formula shows the exact number of atoms of each element in a molecule. The structural formula goes a step further and shows how the atoms are bonded to each other.

We will learn how to find the chemical formula of a compound, based on its constituent elements, differentiate the different ways of representing a chemical formula, and interpret chemical formulas to understand the composition of compounds.

Practical Activity

Activity Title: "Decades and Formulas"

Project Objective

This project aims to deepen students' understanding of the composition and formulation of chemical compounds. It will be an interdisciplinary challenge, addressing concepts in Chemistry and History, where students will research relevant chemical inventions from different decades and their respective chemical compounds.

Detailed Project Description

Students, in groups of 3 to 5, will be tasked with choosing a decade from the 20th century and researching relevant chemical inventions or discoveries from that period. Each group will have to research the compounds involved in these inventions or discoveries and explain the associated chemical formulas. They will need to identify and describe the empirical, molecular, and structural formulas of each compound.

The goal is for students to connect their studies to practical experience, being able to relate the content of chemical formulas to everyday inventions and how our lives have been impacted by them.

Additionally, they should also research the historical and sociocultural context of the time to understand its impact on the inventions.

Required Materials

• Internet access for research
• Writing materials for notes
• Presentation software for slides (optional)

Detailed Step-by-Step for Activity Execution

1. Organize yourselves into groups of 3 to 5 students and choose a decade from the 20th century.
2. Research important chemical inventions or discoveries that occurred during that decade. Choose at least 3 to focus on in your project.
3. For each invention or discovery, identify the main chemical compounds involved and research their empirical, molecular, and structural formulas.
4. Study the meaning of each part of the formula and how they relate to the properties of the compound.
5. Research the historical context of the time and how it may have influenced these inventions.
6. Prepare a presentation compiling your research. Include information about the inventions, the chemical formulas of the compounds, and the historical context.
7. Present your findings to the class.

Project Delivery

At the end of the project, each group must deliver a written report detailing the following topics:

• Introduction: Provide context for the chosen decade, the selected inventions/discoveries, the relevance of these inventions/discoveries in the real world, and the purpose of the project.
• Development: Explain the theory of the worked chemical formula concepts, the research methodology used, a detailed description of each invention/discovery and the chemical compounds involved, as well as a detailed explanation of the chemical formulas (empirical, molecular, and structural). Also, explain the historical context and how it influenced the inventions.
• Conclusions: Summarize the main points, present the learnings obtained, and the conclusions drawn from the project. Consider both the chemical and historical aspects.
• Bibliography: Include all sources of information used during the work.