unit 3 terms

Newland

arranged first 16 elements by increasing atomic mass, law of octaves

Mendeleev

arranged by atomic mass, placed elements in rows with similar properties, switched Tellurium and iodine's places, columns (families) have similar chemical properties

Moseley

arranged by protons and atomic number, X-ray experiments led to discovering the number of protons in the nucleus, moved F block

Periods/Series

horizontal rows on the periodic table in energy levels 1-7

Groups/Families

vertical columns of elements on the periodic table, valence electrons

metals

conduct electricity and heat, malleable, shiny, solid @ room temp

malleable

can be shaped

nonmetals

poor conductors, brittle, gases, solids or liquids @ room temp

transition metals

d block, not as reactive as Groups 1 & 2, can find in nature in pure form, denser metals

rare earth metals

f block, many are not rare, also called Inner Transition Metals

lanthanides

4f – similar reactivity as Group II metals

actinides

5f – all are radioactive, from Pu onward – man-made

alkali metals

soft, silvery metals of low density and low melting points, highly reactive, never found pure in nature

alkaline earth metals

denser, harder, stronger, less reactive than Group 1, too reactive to be found pure in nature -- readily react with air (oxidation)

halogens

combine with most metals to form salts, most reactive of the non-metals

noble gases

unreactive, outermost shell is filled with electrons

hydrogen

behaves like a metal and a nonmetal, most common element in the universe