Module 4 Vocabulary Terms

Chemical Reaction

A process that produces a chemical change

Reactant

Substances that exist before a reaction begins

Product

Substances that form as a result of a chemical reaction

Chemical Equation

Tells chemists at a glance the reactants, products, physical state, and the proportions of each substance present

Physical Change

A change that affects only the physical properties of a substance, such as size or shape

Chemical Change

A change that results in new substances that have different properties from the original substances

Endothermic Reaction

reactions that absorb heat energy

Exothermic Reaction

Reactions that release heat energy

Activation Energy

The minimum amount of energy required to start a chemical reaction

Rate of Reaction

How fast a reaction occurs after it has started

Concentration

The amount of substance present in a certain volume

Inhibitor

A substance that slows down a chemical reaction

Catalsyt

A substance that speeds up a chemical reaction

Enzyme

Large protein molecules in the body that speed up chemical reactions for your cells to work properly