Physical or Chemical Change

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 one or more new substances with different properties.

Front

What is an example of a chemical change?

Back

Burning wood is an example of a chemical change, as it transforms the wood into ash, smoke, and gases.

Front

What happens when sodium is placed in water?

Back

Sodium reacts violently with water, resulting in a chemical change that produces sodium hydroxide and hydrogen gas.

Front

What is an example of a physical change?

Back

Melting ice is an example of a physical change, as it changes from solid to liquid without altering its chemical structure.

Front

What occurs in an instant ice pack when the chemicals mix?

Back

When the chemicals in an instant ice pack mix, a chemical change occurs, resulting in an endothermic reaction that absorbs heat and causes the pack to become cold.

Front

What are the signs of a chemical change?

Back

Signs of a chemical change include color change, temperature change, gas production, formation of a precipitate, and change in odor.

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.

Front

What is an endothermic reaction?

Back

An endothermic reaction is a chemical reaction that absorbs heat from its surroundings, resulting in a decrease in temperature.

Front

What is an exothermic reaction?

Back

An exothermic reaction is a chemical reaction that releases heat, resulting in an increase in temperature.