Chemical Reactions and Physical Changes: What's the Difference?

Chemical Reactions and Physical Changes: What's the Difference?

Lesson Objective

At the end of the lesson, you should be able to describe what a chemical reaction is and describe the difference between a chemical and physical change.

This slide should clearly state the objective of the lesson.

What do you already know about chemical reactions and physical changes?

What is a Chemical Reaction?

A chemical reaction is a process that leads to the transformation of one set of chemical substances to another. Chemical reactions involve the breaking and forming of chemical bonds.

Introduce the topic of chemical reactions and explain what they are.

Examples of Chemical Reactions

Examples of chemical reactions include burning wood, rusting of iron, and cooking an egg.

Provide some examples of chemical reactions for the students to understand the concept better.

What is a Physical Change?

A physical change is a change in which the substance's physical properties change, but its chemical composition remains the same.

Define what a physical change is and how it differs from a chemical change.

Examples of Physical Changes

Examples of physical changes include melting ice, dissolving sugar in water, and boiling water.

Provide some examples of physical changes for the students to understand the concept better.

Chemical Changes vs. Physical Changes

The main difference between chemical changes and physical changes is that chemical changes create new substances, whereas physical changes do not.

Explain the key differences between chemical and physical changes.

Identifying Chemical and Physical Changes

Some signs of a chemical change are the production of gas, light, heat, or a color change. Physical changes, on the other hand, do not produce new substances.

Provide some ways to identify chemical and physical changes.

Review and Summary

In this lesson, we learned that chemical reactions involve the transformation of one set of chemical substances to another and produce new substances. Physical changes, on the other hand, change the substance's physical properties but not its composition. Chemical changes can be identified by the production of gas, light, heat, or a color change.

Recap what the students have learned and reinforce key concepts.

Write down 3 things you learned in this lesson.

Have students enter three things they learned in this lesson. With this they can indicate their own learning efficiency of this lesson.

Write down 2 things you want to know more about.

Here, students enter two things they would like to know more about. This not only increases involvement, but also gives them more ownership.

Ask 1 question about something you haven't quite understood yet.

The students indicate here (in question form) with which part of the material they still have difficulty. For the teacher, this not only provides insight into the extent to which the students understand/master the material, but also a good starting point for the next lesson.