Physical vs. Chemical Changes in Matter

Front

What is a physical change?

Back

A physical change is a change that affects one or more physical properties of a substance without altering its chemical composition. Examples include cutting, bending, or melting.

Front

What is a chemical change?

Back

A chemical change is a change that results in the formation of new chemical substances. It involves a chemical reaction and changes the composition of the original substance. Examples include rusting, burning, and digestion.

Front

Is splitting logs before burning them a physical or chemical change?

Back

Physical change.

Front

What happens during bioluminescence in jellyfish?

Back

Bioluminescence is a chemical change where jellyfish produce light through a chemical reaction involving luciferin and luciferase.

Front

What role do mitochondria play in energy production?

Back

Mitochondria break down glucose in a chemical change to produce usable energy in the form of ATP.

Front

What does it indicate if the temperature decreases when a powder is added to a liquid?

Back

It indicates a chemical change, as the reaction absorbs heat, resulting in a temperature drop.

Front

What is tarnishing of silverware an example of?

Back

Tarnishing is a chemical change where silver reacts with sulfur compounds in the air, forming a black film of silver sulfide.

Front

Can physical changes be reversed?

Back

Yes, many physical changes can be reversed, such as freezing and melting.

Front

Can chemical changes be reversed?

Back

Chemical changes are often not reversible by simple physical means, as they create new substances.

Front

What is an example of a reversible physical change?

Back

An example is the melting of ice into water, which can be frozen back into ice.