Study Guide (Periodic Table and His.) Flashcards
Who attributed to the idea of arranging the known elements of his time in a table according to their chemical/physical properties?
Dmitri Mendeleev
_______ predicted that the empty spaces on his periodic table represented
undiscovered elements
Who arranged the periodic table in the order of Atomic #?
Henry Moseley
The periodic law states there is a periodic repetition of physical/chemical properties of the elements when…
they are arranged in order of increasing atomic #
name of vertical columns of the periodic table…
Groups
Each period in the periodic table corresponds to:
an energy level
Valence electrons:
electrons that are found in the outermost energy level of atoms
the horizontal rows of the periodic table are:
periods
what do elements in the same periodic group have in common
same # of valence configuration, valence electrons, and similar chemical properties
what do elements in the same period have in common
same # of occupied energy levels
how many elements are in a period in which only s and p sublevels are filled
8
sublevels in a period that contains 32 elements
s,p,d,f
(for groups 13-18) # of valence electrons is equal to:
its group # (or group # - 10)
Three classes of elements
metals, nonmetals, metalloids
(elements classes/ fams) Most reactive group of nonmetals
Halogens
(elements classes/ fams) group is unreactive + only found in pure form in nature
Noble gases
(elements classes/ fams) groups name is “basic”
Alkaline Earth Metals
(elements classes/ fams) group of metals contain groups 3-12
transition metals
(elements classes/ fams) group contains most reactive group of metals
alkali metals
(elements classes/ fams) elements are found in second row of f-block elements
actinides
(elements classes/ fams) class of elements have both metallic/ nonmetallic properties
metalloids
(periodic trends) why atomic radius decreases going across the period L to R on periodic table
bc valence electrons are being removed and are closer to positive nucleus (held tighter and harder to remove)
(periodic trends) why atomic radius increases moving down a group of elements
of occupied energy level increases
ionization energy
energy required to remove one electron from an atom
As you move L to R across a period, the first ionization energies
Increases
As you move from top to bottom of group, the first ionization energies
decreases
What is general trend of electronegativity as you go down the group
electronegativity decreases down the group
do metals tend to have high or low electronegativites
Low
What is trend for reactivity for the alkali metals group
reactivity increases going down the group
what is trend for reactivity for the halogens group?
reactivity decreases going down the group
(elements classes/ fams) elements are found in first row of f-block elements
Lanthanides
