Chapter 12 – The Periodic Table

Question Answer
Who is the father of the periodic table? Dmitri Mendeleev
periodic having regular repeated pattern
periodic law the chemical and physical properties of elements are periodic functions of their atomic numbers
period each horizontal row on the periodic table
group a column of elements of the periodic table
alkali metals group 1; 1 electron in the outer shell; very reactive; sodium potassium lithium
alkaline-earth metals group 2; 2 electrons in outer shell; reactive; beryllium magnesium calcium
halogens group 17; 7 electrons in outer level; very reactive; halogen, chlorine, iodine
noble gases group 18; non reactive; neon helium argon
Dmitri Mendeleev constructed the first periodic table
metals most elements are this and are to the left of the zigzag line; few electrons in ourte shell; mostly malleable shiny ductile and good conductors
nonmetals right of line; almost a complete set of electrons; most are gases at room temp.; poor conductors; not shiny; not malleable or ductile
metalloids aka semiconductors and border the zigzag line; 1/2 set of electrons; sometimes act like metals and sometimes like nonmetals
in the modern periodic table the elements are arranged in order of increasing atomic number
a _______ is a representation of an element usually consisting of one or two letters chemical symbol
How is the reactivity of elements related to valance electrons in atoms? the number of valance electrons in an atom of an element determines many properties of that element including the ways in which the atom can bond with other atoms
What does the periodic table tell you about the elements? the periodic table reveals the underlying atomic structure of atoms including the arrangement of the electrons
electron dot diagram this includes the symbol of an element surrounded by dots representing the number of valence electrons