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 melting, freezing, and dissolving.

Front

What is a chemical change?

Back

A chemical change is a change that results in the formation of one or more new substances with different properties. Examples include rusting, burning, and digestion.

Front

Is the formation of the Grand Canyon a physical or chemical change?

Back

Physical change.

Front

What are some signs of a chemical change?

Back

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

Front

True or False: Gases produced in a reaction do not need to be accounted for because they weigh nothing.

Back

False.

Front

What evidence indicates a chemical change has occurred?

Back

Evidence of a chemical change can include gas production, temperature change, and odor.

Front

What is an example of a physical change?

Back

An example of a physical change is ice melting into water.

Front

What is an example of a chemical change?

Back

An example of a chemical change is wood burning to form ash and smoke.

Front

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

Back

The mass of substances is conserved during a chemical change; the total mass of reactants equals the total mass of products.

Front

What is the difference between a reactant and a product?

Back

A reactant is a substance that undergoes a chemical change, while a product is a substance formed as a result of that change.