atom

atom the smallest component of an element having the  chemical properties of the element,  consisting of a nucleus  containing combinations of neutrons and  protons and one or  more electrons bound to the nucleus by electrical attraction; the number of protons determines the identity of the element.  a small particle that is the building block of matter; the smallest piece of an element that still represents that element.

chemical property

chemical property Chemistry. a property or characteristic of a  substance that is observed during a reaction in which the  chemical composition or identity of the  substance is changed.

matter

matter something that has mass and occupies space.

electron

electron an elementary particle having a negative charge and existing independently or as the component outside  the nucleus of an atom.

mass

mass  is a measure of the number of atoms in it.

molecule

molecule the smallest physical unit of an element or compound.

nucleus

nucleus a central part about which other parts are grouped or gathered; core. the positively charged mass within an atom,  composed of neutrons and protons, and possessing most of the mass but occupying only a small fraction of the volume of the atom.

proton

proton a positively charged elementary particle.

temperature

temperature a measure of the warmth or coldness of an object or substance with reference to some standard value. 

physical property

physical property a property (as color, hardness, boiling point) of matter not involving in its manifestation a chemical change.

boiling point

boiling point the temperature at which a liquid boils.

compound

compound composed of two or more parts, elements, or ingredients.

density

density mass per unit volume.

element

element one of a class of substances that cannot be separated into simpler substances by chemical means.

melting point

melting point the temperature at which a solid melts.

neutron

neutron an elementary particle having no charge.

weight

weight the force that gravitation exerts upon a body, equal to the mass of the body times the local acceleration of  gravity.

combustibility

combustibility capable of catching fire and burning;  inflammable; flammable: Gasoline vapor is highly combustible.

malleable

malleable capable of being extended or shaped by  hammering or by pressure from rollers.

vapor

vapor a visible exhalation, as fog, mist, steam,  smoke, or noxious gas, diffused through or suspended in the air.

chemical reaction

chemical reaction a chemical change that occurs when two or more substances combine to form a new substance.

viscosity

viscosity a measurement of a liquid’s resistance to flow.

sublimation

sublimation to pass directly from the solid to the vapor state.

atomic number

atomic number the number of positive charges or protons in the nucleus of an atom, which determines the chemical properties of an element and its place in the periodic table.

conductor

conductor a substance, body, or device that readily  conducts heat, electricity, sound, etc.

pressure

pressure the exertion of force upon a surface by an object, fluid, etc., in contact with it: force per unit area. 

periodic table

periodic table a table illustrating the periodic system, in  which the chemical elements arranged according to their atomic numbers, are shown in related  groups.

condensation

condensation the act or process of reducing a gas or vapor  to a liquid or solid form.

atomic mass

atomic mass the mass of an atom usually expressed in atomic mass units.

evaporation

evaporation to convert into vapor; to expel moisture from.

vaporization

vaporization the rapid change of water into steam,  especially in a boiler.

ductility

ductility capable of being drawn out into wire or  threads, as gold.

concentration

concentration the amount of a component in a given area or volume.

luster

luster the state or quality of shining by reflecting  light; glitter, sparkle, sheen, or gloss.

salinity

salinity consisting of or containing salt.

metal

metal any of various opaque, fusible, ductile, and typically lustrous substances that are good conductors of electricity and heat.

construct

construct to build or form by putting together parts;  frame; devise.