Physical and Chemical Changes

What are the properties of physical changes?

• Irreversible, change in chemical composition, new substances formed

• Reversible, change in chemical composition, new substances formed

• Reversible, no change in chemical composition, no new substances formed

• Reversible, change in physical composition, new substances formed

Give an example of a physical change.

• Mixing salt and water

• Melting of ice

• Boiling water

• Burning wood

How can you reverse a physical change?

• Wait for a natural reversal to occur

• Use the same conditions or forces

• Ignore the change and hope it reverses itself

• Apply opposite conditions or forces

Explain the difference between physical and chemical changes.

• Chemical changes only affect the appearance of a substance.

• Physical changes involve a change in the chemical composition of a substance.

• Physical changes involve a change in the form or appearance of a substance without a change in its chemical composition, while chemical changes result in the formation of new substances with different chemical properties.

• Physical changes result in the formation of new substances with different chemical properties.

Why is the change in state of matter considered a physical change?

• It changes the color of the substance

• It creates a new substance

• It does not alter the chemical composition of the substance.

• It releases a strong odor