Lesson Notes By Weeks and Term - Senior Secondary 2

TERM׃ 1^ST TERM

WEEK FOUR

Class: Senior Secondary School 2

Age: 16 years

Duration: 40 minutes of 5 periods each

Date:        

Subject: Chemistry

Topic: CHEMICAL REACTION 1

SPECIFIC OBJECTIVES: At the end of the lesson, pupils should be able to

1. Define chemical reaction.
2. Discuss the key characteristics of chemical reaction.
3. Define collision theory.
4. Discuss the principles of collision theory and the factors affecting collision theory.

INSTRUCTIONAL TECHNIQUES: Identification, explanation, questions and answers, demonstration, videos from source

INSTRUCTIONAL MATERIALS: Videos, loud speaker, textbook, pictures

INSTRUCTIONAL PROCEDURES

PERIOD 1-2

NOTE

CHEMICAL REACTION 1

A chemical reaction is a process in which one or more substances (reactants) are transformed into new substances (products) with different chemical compositions. During a chemical reaction, bonds between atoms are broken and new bonds are formed, resulting in the creation of different molecules or compounds.

Key characteristics of chemical reactions include:

1. Reactants: The initial substances that undergo the reaction.
2. Products: The substances formed as a result of the reaction.
3. Chemical Equations: Representations of reactions using chemical formulas.
4. Reaction time refers to the duration it takes for a reaction to proceed from the initiation to completion. This can vary widely based on factors like reactant concentrations, temperature, and catalysts.
5. Reaction rate is a measure of how quickly reactants are transformed into products during a chemical reaction. It is often expressed as the change in concentration of reactants or products per unit of time. Reaction rates can be influenced by factors such as temperature, concentration, surface area, and the presence of catalysts.

Introduction to collision theory

Collision theory is a fundamental concept in chemistry that explains how chemical reactions occur at the molecular level. Proposed by Max Trautz and William Lewis in the early 20th century, collision theory provides insights into the factors influencing reaction rates.

Key Principles of Collision Theory:

1. Molecular Collisions: According to collision theory, for a chemical reaction to occur, molecules must collide. However, not all collisions lead to a reaction; certain conditions must be met for a collision to be successful.
2. Activation Energy: Molecules possess a certain amount of kinetic energy due to their motion. However, not all collisions have enough energy to overcome the activation energy barrier, a minimum energy required to initiate a chemical reaction.
3. Orientation of Collisions: Successful collisions also depend on the proper orientation of molecules. For many reactions, molecules must collide in a specific way to allow bonds to break and form.

Factors Influencing Reaction Rates According to Collision Theory:

1. Temperature
2. Concentration
3. Surface Area
4. Catalysts

Limitations of Collision Theory

While collision theory provides valuable insights into reaction kinetics, it does have limitations. It assumes that molecules are hard spheres, neglecting factors like molecular shape and electronic effects. Quantum mechanics and more advanced theories are required for a more detailed understanding of molecular interactions.

NOTE: collision theory is a conceptual framework that helps explain the factors determining the rates of chemical reactions. By considering collision frequency, energy, and orientation, this theory provides valuable insights into the dynamics of molecular interactions in chemical processes.

EVALUATION :  - Define Chemical reaction.

                            -  What is collision theory.

                            - Explain two key principles of collision theory.

                            - What are the factors influencing reaction rate according to collision theory.                 

CLASSWORK: As in evaluation

CONCLUSION: The teacher commends the students positively