Exploring Matter: Changes and Properties

Front

What is a chemical change?

Back

A process where substances combine or break apart to form new substances with different properties.

Front

What evidence indicates a chemical change has occurred?

Back

Production of heat and light, formation of a precipitate, color change, or gas production.

Front

What is an exothermic reaction?

Back

A chemical reaction that releases heat, making the surroundings warmer.

Front

What is an endothermic reaction?

Back

A chemical reaction that absorbs heat, making the surroundings cooler.

Front

What happens to the properties of substances during a chemical change?

Back

The properties change because new substances are formed.

Front

What is a precipitate?

Back

A solid that forms and settles out of a liquid mixture during a chemical reaction.

Front

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

Back

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

Front

What is rusting?

Back

A chemical change where iron reacts with oxygen and moisture to form iron oxide (rust).

Front

What is combustion?

Back

A chemical change that occurs when a substance reacts rapidly with oxygen, producing heat and light.

Front

What is the law of conservation of mass?

Back

In a chemical reaction, mass is neither created nor destroyed; it is conserved.