Energy and Reactions In a chemical reaction bonds are either formed or broken Bonds are a form of energy All reactions result in either the absorption or release of energy

Exergonic Reactions What are some words that begin with ex? What does ex mean? out of, from, out Exergonic reaction is the release of or (exit) of energy in the form of heat or light

Triboluminescence - A type of exergonic reaction Light that results from scratching or abrading a substance as when two pieces of quartz are rubbed together to produce light. Another example the wintergreen lifesaver

Chemiluminescence-A type of exergonic reaction Chemiluminescence is the production of light by a chemical reaction during which chemical energy is converted to light energy. An example are light sticks

Bioluminescence Bioluminescence is the production and emission of light caused by chemical reactions in living things

Bioluminescence Bioluminescence can be used for camoflague, attraction, repulsion, and communication.

Jellyfish

Sea Slug (Phyllirhoe)

Firefly

Fireflies

Phosphorescence Energy from an external source is absorbed Glow in the dark stars, stickers, etc. Phosphorescent substances have the ability to store up light and release it gradually.

Exothermic reaction Exothermic reactions - release thermal energy. Heat is exiting the reaction, therefore it feels warm/hot to the touch

Endergonic Reaction Endergonic reaction - absorbs energy in the form of heat, light, or electricity Energy enters the reaction Endothermic reaction - A type of endergonic reaction. Heat needs to be added to the reaction. Heat enters the reaction. Sometimes feels cool/cold to us.