Unit 4 Vocabulary for Science

Term Definition
Atomic Mass Average mass of one atom of an elements
Periodic Table A Chart where all elements are organized into periods and group according to thier to thier properties
Chemical Symbol One or two letter code that stands for an element; many sumbols are abbrievation of the elements name, which may be latin, english, or greek in origin
Period A row of elements in the periodic table arranged by atomic number
Group Column of elements in the periodic table, in which elements have certain properties in common; also called chemical family
Matter The material that all objects and substances are made of; anything that has a mass and takes up space
Element Substances that are the building block or all matter; an element is made up of one kind of atom
Compound Matter made of two or elements; the elements in a compound are chemically bonded, cannot be seperated by physical means, and a compound has properties that are different from the elements that make it up
Atom Smallest particle into which an element can be divided and still have the properties of that element
Electron Negatively charged particle found outside the nucleas of a proton
Nucleas Center of an atom made up of protons and neutrons
Proton Positively charged particle in the nucleas of an atom
Neutron In a atom, particle with a neutral charge; located in the nucleas
Energy Level The amount of energyh carried by an electron in an atom; determines the electron's average distance from nucleas
Isotype Atoms of the same element with different numbers of neutrons in hte nucleas, and thus different atomic masses for example, carbon-12
Mass Number The sum of protons and neutrons in the nucleas of an atom
Atomic Number The number of protons in the nucleas in the nucleas of a atom
Metal A class of elements characterized by physical properties: shiniess, malleability, ductility, conductivity
Malleble A term used to describe material that can be pounded into shapes
Ductile Term to describe a material that can be strecthed into a long object
Conductivity The ability of a n object to transfer heat to another object
Reactivity The ease or speed with an element comines or reacts, with other elements or compound
Corrosino The gradual wearing away of metal element element due to chemical reaction
Alkai Metal An element in group 1 of the periodic table
Alkaline Earth Metal An element in group 2 of the periodic table
Transition Metal One of the element in group 3 through 12 of the periodic table
Alloy A mixture of two or more elements, one of which is a metal
Non-Metal An element that lacks most of the properties of a metal
Diatomic Molecule A molecule consiting of two atoms
Halogen An element foung in group 17 of the periodic table
Metaloid An element that has some characteristics of both metal and non-metals.
Noble Gas An element foung in group 18 of the periodic table
Semi-Conductor A substance that can conduct electricity under some conditions