Energy in Reactions

Vocabulary flashcards defining key concepts related to chemical reactions, energy changes, activation energy, and biological energy sources from the text.

Activation Energy

The energy that is needed to get a chemical reaction started, defined as the difference between the peak energy required for the reaction to go forward and the energy of the reactants.

Energy-Releasing Reaction

A chemical reaction that releases energy and often occurs on its own, or spontaneously, such as the burning of hydrogen gas ($2H_2 + O_2 \rightarrow 2H_2O$).

Energy-Absorbing Reaction

A chemical reaction that absorbs energy and will not occur without a source of energy, such as decomposing water into hydrogen and oxygen gas via an electrical current.

Metabolize

The process of breaking down digested food through chemical reactions to release energy needed for an organism to live.

Plant Energy Sources

The mechanism by which plants acquire energy by trapping and storing sunlight energy in energy-rich compounds.

Animal Energy Sources

The mechanism by which animals acquire energy by consuming plants or other animals.

Energy Changes in Chemical Reactions

The release or absorption of energy that occurs whenever chemical bonds are formed or broken during a reaction.