The extent to which a measurement is in proximity to the standard or expected value.
A substance that increases the H+ concentration when added to a water solution.
The least amount of energy required to start a particular chemical reaction.
A particular development, behavior, or physiological change in a population of organisms, in response to changes in the populations.
An organic molecule containing an amino (-NH2) and a carboxyl (-COOH) group from which proteins are synthesized.
A solution containing water.
The average distance from Earth to the Sun, approximately 150 million kilometers.
The number of protons in an atom's necleus; the atomic number determines an element's placement on the periodic table.
A substance that increases the OH concentration of a solution; a proton acceptor.
A complex biotic community characterized by the interaction of living organisms and climatic factors.
A substance that speeds up or slows down the rate of reaction without being consumed or altered.
The motion away from center or axis.
The force on an object required to keep this object on a circular path, pulling toward the center of the circle.
A substance made up of at least two different elements held together by chemical bonds that can only be broken down into elements by chemical processes.
The relative amount of a particular substance, a solute, or mixture.
conservation of mass
The principle that mass cannot be created or destroyed; also conservation of matter.
Area where two tectonic plates collide.
A chemical bond between two atoms of the same or different elements in which each atom shares an electron.
The bending of a wave around an obstruction.
A nucleic acid that carries genetic material; present in all cellular organisms.
A magnet consisting of a coil of wire wrapped around a core that becomes strongly magnetized when current flows through the coil producing a magnetic field.
Waves generated by the oscillaton of a charged particle and characterized by periodic variations of electric and magnetic fields.
A rock fracture along which movement or displacement of Earth's crust has taken place.
first law of thermodynamics
A law that states the internal energy in a system remains constant and the change in thermal energy of a system is equal to the work done on the system.
The sum total of the genetic information contained in an organism.
The amount of time required for half of an original sample of radioactive material to decay or undergo radioactive transformation.
heat of fusion
The amount of heat energy required to convert a unit mass of substance from a solid to a liquid through melting at a constant temperature and pressure.
heat of vaporization
The amount of heat energy needed to change a unit mass of substance from a liquid to a gas at its boiling point.
A chemical compound that changes color depending on the pH of the solution or other chemical change.