matter physical property - any property that can be observed or measured without altering a substance’s chemical composition density - the amount of matter in a unit of volume conductivity - the property of a material that enables it to transfer thermal energy or electricity chemical property - any property that describes the way that matter actcs in the presence of other materials - the way that matter changes composition under certain conditions reactivity - the property of a substance that enables it to interact with another specific chemical flammability - the property of a substance that enables it to burn in the presence of oxygen chemical change - any change that causes a substance to change its chemical identity - also known as a chemical reaction mixture - the combination of two or more substances that are physically combined in a changeable ratio - heterogeneous mixtures have two or more distinct regions, giving it a nonuniform appearance - homogeneous mixtures have only one phase, which gives it a uniform appearance filtration - a process for separating mixtures on the basis of particle size distillation - a process for separating a mixture based on the different boiling points of its components decanting - a process for separating mixtures in which a less dense medium is poured off the top of a more dense medium element - a pure substance that consists of only one kind of atom atom - the smallest particle that makes up an element and is capable of chemical interactions nucleus - the extremely small and dense center of an atom that contains the protons - protons are positively charged subatomic particles - neutrons are uncharged (neutral) subatomic particles - electrons are negatively charged subatomic particles - surrounded by an electron cloud ion - an atom with an unbalanced (not equal) number of protons and electrons - net electrical charge a charged atom (or group of atoms) due to the gain/loss of electrons chemical symbol - a one- or two-letter symbol that identifies an element - often (but not always) the first letter of the element’s name molecule - a distinct group of atoms that are covalently bonded together compound - a pure substance that consists of two or more elements chemically combined in a fixed ratio chemical formula - a combination of chemical symbols, coefficients, and subscripts - identifies the elements and number of atoms of each element in a compound work - done anytime an object moves while a force is applied along its direction of motion energy is the ability to do work - work and energy are both measured in joules (“J”) kinetic energy - the energy that an object has due to its motion potential energy - the energy that an object has due to its position or condition mechanical energy - the sum of an object’s kinetic and potential energies thermal energy - the sum of the kinetic energies of all the particles within a substance chemical energy - the potential energy stored in chemical substances thermodynamics - the study of the movement and conversion of energy; especially thermal energy
