Physical vs chemical change flashcards

What is a physical change?

A physical change alters a substance's appearance but not its composition. Examples include melting ice or tearing paper.

What is a chemical change?

A chemical change results in new substances being formed. Examples include burning wood or rusting iron.

True or false: Freezing water is a chemical change.

False, because freezing water only changes its state, not its chemical makeup.

Difference between melting and burning.

Melting is a physical change; burning is a chemical change that creates new substances.

Fill in the blank: Rusting iron is a _____ change.

chemical change, as it creates iron oxide.

Question: Is dissolving sugar in water a physical change?

Yes, because the sugar can be recovered by evaporating the water.

What happens during a chemical change?

Atoms rearrange to form new substances. Energy is often released or absorbed.

True or false: Cutting wood is a physical change.

True, because the wood's composition remains the same.

What is an example of a physical change?

Examples include breaking glass or chopping vegetables.

Difference between evaporation and combustion.

Evaporation is a physical change; combustion is a chemical change with new products.

Question: Can chemical changes be reversed?

Not usually, but some can be reversed through further chemical reactions.