Unit 1 Review - Chemical and Physical Changes

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 melting, freezing, and dissolving.

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 the breaking and forming of bonds. Examples include burning, rusting, and baking.

Front

What happens when blue and yellow liquids are mixed?

Back

When blue and yellow liquids are mixed, they undergo a physical change to form a green liquid, as the substances retain their original chemical properties.

Front

What occurs during the melting of ice?

Back

The melting of ice is a physical change where solid ice turns into liquid water without changing its chemical structure.

Front

What is produced when baking soda and vinegar are combined?

Back

When baking soda and vinegar are combined, a chemical change occurs, producing carbon dioxide gas, water, and sodium acetate.

Front

What is an example of a chemical change involving combustion?

Back

Burning coal is an example of a chemical change, as it reacts with oxygen to produce carbon dioxide, heat, and ash.

Front

What happens to cake batter when it is baked?

Back

When cake batter is baked, a chemical change occurs as the ingredients react to form a new substance: the baked cake.

Front

What is the difference between a physical change and a chemical change?

Back

A physical change alters the form or appearance of a substance without changing its chemical composition, while a chemical change results in the formation of new substances.

Front

Can a physical change be reversed?

Back

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

Front

Can a chemical change be reversed?

Back

Chemical changes are often not reversible by simple physical means, as they involve the formation of new substances.