matter
anything that occupies space and has mass
density
a measure of the concentration of matter; it is expresses as a ratio of the object's mass to its volume
physical property
a property of matter that results from the position and characteristics of its particles and that can be measured without causing a change in the identity of the material
malleability
a physical property of matter indicating the capability of matter to be shaped by pounding
ductility
a physical property of matter describing its ability to be drawn into a wire
conductivity
a physical property of matter indicating the ability to transfer heat or electrons through a substance
chemical change
a change in which a substance loses its characteristics and becomes one or more new substances
physical change
a change that alters the physical properties of a substance but that does not change its identity
chemical reaction
changes in the identity of a material that result in a different material with different composition and different properties
pure substance
a substance that is made up of only one kind of particle and has uniform composition
element
a substance that cannot be broken down by ordinary chemical means into anything that is both stable and simpler and whose atoms all have the same atomic number
solution
a homogeneous mixture of two or more substances
atom
a neutral particle with a centrally located nucleus consisting of protons and neutrons with electrons around it. The smallest representative unit in an element.
monatomic element
an element whose atoms exist independently
diatomic element
an element whose atoms bond into two atom units
polyatomic element
an element whose atoms bond in multi-atom units
symbol
one or two letter representation for an element
compound
a substance that consists of atoms of different elements chemically bonded together
formula
a combination of subscripts and chemical symbols that indicate the number and kinds of atoms that are present in a compound
subscript
a number written at the lower right of a chemical symbol in a formula to indicate the number of components immediately preceding it
coefficient
a number that appears in front of a chemical formula and indicates how many units of that substance are present
molecule
two or more covalently bonded atoms found as a separate, distinct, independent unit
mixture
two or more pure substances physically combined with no definite proportions
heterogeneous mixture
a mixture composed of two or more distinctly separate phases that have their own properties
homogeneous mixture
a mixture existing in only one distinctly separate region with its own porperites
exothermic
a term describing a process that releases heat energy
endothermic
a term describing a process that absorbs heat energy
energy
the ability to do work
thermodynamics
the study of energy transformations in chemical and physical processes
first law of thermodynamics
the physical law that states that energy cannot be created nor destroyed but can be converted from one form into another
second law of thermodynamics
the physical law that states that during any energy transformation, some energy goes to an unusable form
law of mass/energy conservation
a corollary to the first law of thermodynamics; during ordinary physical and chemical process, mass is neither created nor destroyed, only converted from one form to another.
kinetic energy
energy due to motion
thermal energy
the measure of the total kinetic energy of the molecules or ions in matter, usually measured in calories
entropy
the measure or randomness or disorder in a specified portion of the universe; a measure of the increasing unavailability of energy to perform useful work
heat
thermal energy in transit from one object to another
temperature
a measure of the average kinetic energy of the atoms, molecules, or ions in matter
calorie, Calorie
the amount of energy required to raise the temperature of 1 gram of water 1 *c Calorie is 1 kilo calorie.
BTU
the quantity of heat energy required to raise one pound of water by 1 *F
Celsius scale
a temperature scale proposed by Anders Celsius that divides the range from the freezing point of water (0
C) to the boiling point of water (100
C). It also labels absolute zero as -273 *C.
Kelvin scale
a temperature scale that divides the rage from the freezing point of water (273 K) to the boiling point of water (373 K). It labels absolute zero as 0 K.
Fahrenheit scale
a temperature scale proposed by Gabriel Fahrenheit. It has 180 divisions between the freezing point of water (32
F) and the boiling point of water (212
F)
absolute zero
o K, the temperature at which all molecular motion would cease; the coldest temperature possible
kinetic theory
a theory that states that the particles of matter are in constant motion and that the properties of matter are consequences of that motion
solid
a state of matter in which the particle have relativity little energy and cannot overcome the attractive forces
liquid
a state of matter in which the particle have enough energy to partially overcome the attractive forces; the liquid will conform to the shape of its container
gas
a state of matter in which the particles have enough energy to overcome the attractive forces; gas has no definite size or shape
plasma
the most abundant form of matter, consisting of gaseous sea of high-velocity electrons, ions, and neutral atoms
Bose-Einstein Condensate
the theoretical fifth state of matter that will exist at absolute zero
condensation
a physical change from the gaseous state to the liquid state
freezing
a physical change from the liquid state to the solid state
melting
a physical change from the solid to the liquid state
sublimation
a physical change directly between the solid and gaseous states