Physical and Chemical 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 changes in size, shape, or state of matter.

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 digestion.

Front

What is a sign that a chemical reaction has occurred?

Back

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

Front

Give an example of a chemical change.

Back

Wood burning is an example of a chemical change, as it transforms into ash and gases.

Front

What indicates a physical change?

Back

A change in size is an indication of a physical change, as it does not alter the substance's chemical identity.

Front

Which of the following is NOT a physical change?

Back

Rust is not a physical change; it is a chemical change that occurs when iron reacts with oxygen.

Front

What happens when sugar dissolves in water?

Back

When sugar dissolves in water, it undergoes a physical change, as the sugar molecules disperse in the water but do not change chemically.

Front

What is the difference between physical and chemical changes?

Back

Physical changes do not alter the chemical composition of a substance, while chemical changes result in new substances being formed.

Front

What is an example of a physical change?

Back

Ice melting is an example of a physical change, as it changes from solid to liquid without changing its chemical structure.

Front

What is a precipitate?

Back

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