8.5E Evidence of Chemical Reactions

Front

What is a physical change?

Back

A change in the size, shape, or state of matter without altering its chemical composition.

Front

What is a chemical change?

Back

A process where substances combine or break apart to form new substances with different properties.

Front

What evidence indicates a chemical reaction has occurred?

Back

Evidence includes changes in temperature, color, gas production, or the formation of a precipitate.

Front

What is an exothermic reaction?

Back

A chemical reaction that releases heat, resulting in an increase in temperature.

Front

What is an endothermic reaction?

Back

A chemical reaction that absorbs heat, resulting in a decrease in temperature.

Front

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

Back

The mass of the reactants equals the mass of the products, according to the law of conservation of mass.

Front

What is a reactant?

Back

A substance that undergoes a chemical change in a reaction.

Front

What is a product?

Back

A substance that is formed as a result of a chemical reaction.

Front

What is an indicator of a chemical change?

Back

Indicators include color change, temperature change, gas production, and the formation of a solid.

Front

What is rusting?

Back

A chemical change where iron reacts with oxygen and moisture to form iron oxide (rust).