Physical and Chemical Changes in Everyday Life

The video from FreeSchool explains the differences between physical and chemical changes. Physical changes alter the form or appearance of a substance without forming a new substance, and they are often reversible. Examples include cutting cloth and changing states of water. Chemical changes result in the formation of new substances and are usually irreversible, such as burning wood or baking a cake. The video provides clues to distinguish between these changes, emphasizing that chemical changes often involve color change, odor, gas release, and energy change.

What are the two main categories of changes in materials discussed in chemistry?

• Physical and Biological changes

• Chemical and Biological changes

• Physical and Chemical changes

• Biological and Environmental changes

Which of the following is an example of a physical change?

• Baking a cake

• Melting ice

• Rusting metal

• Burning wood

Why is dissolving sugar in water considered a physical change?

• Because sugar and water can be separated

• Because it releases heat

• Because it creates a new substance

• Because it cannot be undone

What indicates that a chemical change has occurred when baking a cake?

• The mixture can be easily separated

• The cake can be unbaked

• The mixture absorbs heat and changes color

• The ingredients remain unchanged

Which of the following is NOT a characteristic of a chemical change?

• Release of gases

• Can be easily reversed

• Change in color

• Formation of a new substance

What happens to wood when it undergoes a chemical change?

• It evaporates

• It turns into water

• It becomes ash

• It melts

Which of the following is an example of a chemical change?

• Melting ice

• Cutting paper

• Burning wood

• Mixing sand and water

What is a clue that a chemical change has occurred?

• The substance remains the same

• The substance releases light

• The substance changes state

• The substance changes shape

Which of the following changes can usually be undone?

• Neither chemical nor physical changes

• Chemical changes

• Both chemical and physical changes

• Physical changes

What is a common feature of physical changes?

• They are irreversible

• They release gases

• They change the state of matter

• They form new substances