Physical Chemical Change Practice

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 changes such as rusting, burning, and souring of milk.

Front

What are signs of a chemical reaction?

Back

Signs of a chemical reaction include: 1) Change in color, 2) Production of gas (bubbles), 3) Formation of a precipitate, 4) Change in temperature.

Front

Is melting ice a physical or chemical change?

Back

Melting ice is a physical change because it changes from solid to liquid without altering its chemical composition.

Front

What happens during a chemical change?

Back

During a chemical change, the bonds between atoms in a substance break and new bonds form, resulting in the creation of new substances.

Front

What is an example of a physical change?

Back

An example of a physical change is breaking a cracker into pieces. The composition of the cracker remains the same.

Front

What is an example of a chemical change?

Back

An example of a chemical change is the souring of milk, which results in new substances being formed.

Front

What does it mean when gas bubbles appear during a reaction?

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The appearance of gas bubbles is a sign that a chemical reaction has occurred, indicating that new gases are being produced.

Front

What is the difference between physical and chemical changes?

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

Front

What is a precipitate?

Back

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