8.PS.6 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 includes processes like burning, rusting, and souring.

Front

Which process is an example of a physical change?

Back

Ice melting is an example of a physical change.

Front

What is matter?

Back

Matter is anything that has mass and takes up space.

Front

What are the three main states of matter?

Back

The three main states of matter are solid, liquid, and gas.

Front

What is an element?

Back

An element is a pure substance that cannot be broken down into simpler substances by chemical means. Examples include oxygen, hydrogen, and gold.

Front

What is a compound?

Back

A compound is a substance formed when two or more elements are chemically bonded together. Examples include water (H2O) and carbon dioxide (CO2).

Front

What is a homogeneous mixture?

Back

A homogeneous mixture is a mixture in which the composition is uniform throughout. Examples include saltwater and air.

Front

What is a heterogeneous mixture?

Back

A heterogeneous mixture is a mixture in which the composition is not uniform throughout. Examples include salad and sand.

Front

What are signs that a chemical change has occurred?

Back

Signs of a chemical change include color change, formation of gas (bubbles), energy change (heat or light), and the formation of a precipitate.