Physical and Chemical Changes

Front

What is a physical change?

Back

A physical change is a change in the state or appearance of a substance without altering its chemical composition.

Front

Why is melting ice considered a physical change?

Back

Melting ice is a physical change because it involves a change in state from solid to liquid without creating a new substance.

Front

What happens to thermal energy when a liquid freezes?

Back

Thermal energy is removed from the liquid during the freezing process.

Front

What is a chemical change?

Back

A chemical change is a process that involves the transformation of one or more substances into different substances, often accompanied by energy changes.

Front

What is another term for a chemical change?

Back

Another term for a chemical change is a chemical reaction.

Front

What is rusting?

Back

Rusting is a chemical change that occurs when iron reacts with oxygen and moisture, forming iron oxide.

Front

What is an example of a physical change?

Back

An example of a physical change is the dissolving of sugar in water.

Front

What occurs during the process of dissolving?

Back

During dissolving, the solute (e.g., sugar) breaks down into smaller particles and becomes evenly distributed in the solvent (e.g., water) without changing its chemical structure.

Front

What are the signs of a chemical change?

Back

Signs of a chemical change include color change, gas production, temperature change, and the formation of a precipitate.

Front

Can physical changes be reversed?

Back

Many physical changes can be reversed, such as freezing and melting, but some may not be easily reversible.