26 terms

7th Grade Science: Periodic Table

Sci7 Ch 4.1 and 4.2 of Matter Book
a substance that can't be broken down into a simpler substance; made up of tiny particles called atoms
Atomic Number
number of protons in an atom
Atomic Mass
number of protons + neutrons in an atom
Unit of measurement for atomic mass. Each Proton and Neutron has a mass of 1 AMU
Bohr model
shows all electrons in an atom orbiting in defined paths at specific distances (shells) like planets around our sun
atoms of the same element with different numbers of neutrons (so the mass numbers are different). For example Nitrogen-14 and Nitrogen-15
Electron Cloud
space around the nucleus where electrons are likely to be found
name for the vertical columns on the periodic table
name for the horizontal rows on the periodic table
material which has the properties of both a metal and a nonmetal
Lewis Structure
Model of an atom showing only the outermost (valence) electrons
A group of elements on the periodic table that have similar physical and chemical properties
Russian chemist who developed a periodic table of the chemical elements and predicted the discovery of several new elements (1834-1907)
Element that is malleable, ductile, a good conductor of electricity, and generally has a shiny luster.
The appearance or quality of light reflected from the surface of an object
capable of being drawn out, as to create a wire
Easy to shape or bend
alkali metal
one of the very reactive metals of group 1 of the periodic table (lithium, sodium, potassium, rubidium, cesium, and francium)
alkaline Earth metal
metallic elements in group 2 of the periodic table which are harder than the alkali metals and are also less reactive
transition metal
metallic elements in groups 3-12 of the periodic table, 1-2 electrons in the outer energy level, less reactive than alkali-earth metals, shiny, good conductor of thermal energy and electrical current, high density
boron family
elements in group 13 of the periodic table, 3 valance electrons, both metals and metalloids
carbon family
elements in group 14 of the periodic table, 4 valance electrons, Carbon (C) at the top, Lead (Pb) at the bottom
oxygen family
Group six. Has 6 valence electrons in outer shell. Need to gain or share 2 electrons to become stable.
halogen family
the elements in group 17 of the periodic table and has 7 valence electrons and typically gains or shares one electron when it reacts
noble gas
Elements in group 8A of the periodic table. Have no charge and are gases under normal conditions. (Helium, Neon, Argon, Krypton, Xenon, Radon)
rare Earth element
seventeen chemical elements that commonly occur together but are difficult to separate. They are commonly used to make high tech electronics and weapons systems.