Lesson 1: Definition, Scope, Interrelations

Video Lesson

Competencies

At the end of this lesson, you will be able to:

• Define chemistry
• Describe the scope of chemistry
• Discuss the relationships between chemistry with physics, Biology, medicine geology and other subjects.

Brainstorming Questions

1. How does understanding the properties and transformations of matter impact our everyday lives?
2. Why is chemistry often referred to as the ‘central science,’ and how does it connect with other scientific disciplines like biology, physics, and geology?
3. How does analytical chemistry contribute to ensuring food safety and quality in Ethiopia?

Key Terms

1.1. Definition Of Chemistry

Have you ever pondered how things around us are made? The fundamental principles of everything in our universe can be understood through the study of chemistry. Let me ask you to consider the following: “What comes to your mind when you hear the word ‘chemistry’?”

Now, Let’s define what Chemistry is all about.

Chemistry is a fascinating branch of science that explores the properties, composition, structure and transformation of substances. It helps us understand why substances react with each other and how they change into different forms. But what exactly does that mean?

In our everyday lives, we encounter various substances like gold, silver, water, soap, and table salt, etc. ,which are all examples of matter,and matter is anything that occupies space and has mass.

Imagine holding a book or using a pencil – these are all forms of matter. Matter is made up of very small particles called atoms. We shall discuss atoms in Unit 3 of this Module 1.

Let’s elaborate on the concepts of properties, structure, composition, and transformation of substances:

The properties of substances refer to characteristics or attributes that can be used to describe and identify different substances. Each substance around us has unique qualities that distinguish it from others. For instance, water is colorless, tasteless, and takes the shape of its container. These attributes define the properties of water. Properties are like the fingerprints of substances – they help us identify and understand them better.

Structure refers to how the atoms and molecules are arranged within a substance. This can include bonding patterns, crystal structures, and overall organization at the molecular level. The arrangement of elements within a substance forms its structure. Just like a school building is made up of walls, doors, and windows arranged in a specific way, substances have their own unique arrangements that determine how they behave and interact with other substances.

The composition of a substance refers to the specific elements or compounds it is made of. The composition of a substance can vary, leading to different properties. For example, water (H₂O) has a different composition than hydrogen peroxide (H₂O₂), which accounts for their different chemical properties.

Transformation of substances refers to the changes that occur in a substance when it undergoes a physical or chemical change. For example, when water is heated, it transforms from a liquid to a gas (water vapor) through the process of evaporation. This transformation is a physical change because the chemical composition of water remains the same.

1.2. Scope Of Chemistry

Have you ever wondered how substances around us interact and change? Chemistry helps us explore and understand these processes. Let’s delve into the different branches of chemistry and how they impact our lives.

1.2.1. Main Branches Of Chemistry

Chemistry can be divided into several main disciplines, each focusing on different aspects of matter and substances:

1. Physical Chemistry:

• Studies the properties and behavior of matter at a molecular and atomic level.
• Rates of chemical reactions and energy changes during these reactions are studied under Physical Chemistry.
• In Ethiopia, understanding energy transfer in chemical reactions can help improve energy technologies.

2. Organic Chemistry:

• Focuses on carbon-containing compounds, which are essential for life.
• Ethiopia, with its diverse plant life, benefits from organic chemistry in agriculture and traditional medicine.

3. Inorganic Chemistry:

• Deals with substances that do not contain carbon, such as minerals and metals.
• Important for materials used in construction and technology, which are crucial for Ethiopia’s development.

4. Analytical Chemistry:

• Concerned with identifying and quantifying the composition of substances.
• Helps ensure the quality of food and medicines through rigorous testing.

5. Biochemistry:

• Investigates chemical processes within living organisms.
• Advances in biochemistry can lead to better healthcare solutions and agricultural practices in Ethiopia.

1.2.2. Scope Of Chemistry

Chemistry influences various aspects of life and natural events in Ethiopia:

Agriculture:

Chemistry improves soil quality and helps develop fertilizers to increase crop yields.

• Medicine: Chemists contribute to developing drugs and understanding disease processes for better healthcare.
• Food Production: Ensures food safety through analysis of additives and contaminants.
• Building Construction: Develops new materials that are durable and environmentally friendly.

The applications of Chemistry extends across agriculture, medicine, technology, and environmental science, contributing to societal progress. However, chemical innovations also pose risks, leading to hazardous substances that can adversely impact human health and the environment.

In conclusion, chemistry plays a crucial role in understanding and improving our world. By studying its different branches, we can solve challenges in agriculture, medicine, food production, and construction. Chemistry is not just about theories – it’s about practical applications that benefit society and the environment.

By learning about these disciplines, we can appreciate how chemistry shapes our everyday lives and prepares us for future opportunities in Ethiopia and beyond.

1.3. Natural Sciences and Chemistry

Science is the process by which we learn about the natural universe by observing, testing, and then generating models that explain our observations.

The vastness of the physical universe has led to the development of various scientific disciplines.

• Chemistry explores the nature of matter,
• Biology focuses on living organisms,
• Physics investigates physical phenomena such as matter, energy, and forces, and
• Geology examines rocks and the Earth’s structure

1.3.1. Chemistry As The Central Science

Although we divide science into different fields, there is much overlap among them. Chemistry plays a crucial role as the ‘central science’ due to its interconnections with various other scientific disciplines. Biology, geology, physics, and medicine all intersect with chemistry, forming specialized fields such as biochemistry, geochemistry, and physical chemistry.

1. Biochemistry exemplifies the overlap between chemistry and biology, studying chemical processes within living organisms. For instance, chemists working in biochemistry research medicinal compounds derived from plants.
2. Geochemistry combines geology and chemistry to study the distribution and composition of chemical compounds in geological environments.
3. Physical chemistry applies principles from physics to study chemical systems, focusing on topics such as reaction rates, energy transfers, and molecular structures.
4. Chemical physics integrates techniques from atomic and molecular physics, as well as condensed matter physics, to investigate physicochemical phenomena.
5. Medicinal chemistry bridges chemistry and medicine, focusing on the development and study of pharmaceuticals.