26.5. E http://www.ck12.org
electron
Negatively charged atomic particle outside the nucleus of an atom.
electron cloud
Area surrounding the nucleus of an atom where electrons are likely to be.
electronics
Use of electric current to encode information.
element
Pure substance that cannot be separated into any other substances.
endothermic reaction
Chemical reaction that needs a constant input of energy to continue because it takes more energy to break
bonds in the reactants than is released when new bonds form in the products.
energy
Ability to cause changes in matter.
energy conversion
Process in which energy changes from one type or form to another.
energy level
Areas located at fixed distances from the nucleus of an atom where electrons can orbit the nucleus.
engineer
Professional in technology.
enzyme
Biochemical catalyst that speeds up chemical reactions in living things.
equilibrium
Balance between opposing changes, such as the forward and reverse directions of a chemical reaction.
ethics
Rules for deciding between right and wrong.
evaporation
Process in which a liquid changes to a gas without boiling.
exothermic reaction
Chemical reaction that releases energy because it takes less energy to break bonds in the reactants than is
released when new bonds form in the product.
experiment
Controlled scientific study of a limited number of variables.