Chapter 6-Periodic Table Flashcards
Current periodic table is who’s model? What did he arrange the elements by?
Henry Moseley
atomic number
each box of the periodic table has…
element name
symbol
atomic number
atomic mass
period vs group
period: row
group: column
Representative elements
s and p blocks
possess wide range of chemical and physical traits
transition elements
d and f blocks
metals
usually solid at room temp
good heat and electricity conductors
Where are the metals located?
Left of staircase
Malleability
ability to be pounded thin
Ductility
ability to be drawn into wires
alkali metals
group 1 elements
very reactive
usually exist as compounds with other elements
alkaline earth metals
group 2 elements
very reactive
transition elements divided into ___ and ___
transition metals and inner transition metals
inner transition metals divided into ___ and ___, which are located in the ___ block
lanthanide series and actinide series
f block
nonmetals located…
right of staircase
nonmetals
usually gases or dull-looking solids
poor heat and electricity conductors
which nonmetal is the only one that’s liquid at room temp?
bromine
halogens
group 17
very reactive
often form compounds with other elements
noble gases
group 18
metalloids/semimetals
elements bordering staircase
physical and chemical traits of both metals and nonmetals
only metal that is liquid at room temp?
Mercury
counting valence e’s
look at s and p blocks (count in)
noble gases have __ valence e’s each
8
atomic radius
metals: 1/2 distance between a crystal’s adjacent nuclei
nonmetals: 1/2 distance between nuclei of identical atoms
trend of atomic radii from left to right
decrease
# of protons increase from left to right more protons have stronger pull on negative e's (increased positive charge on nucleus) atoms become more constrained
trend of atomic radii down a column
increase
more energy levels
although there are more e’s, they’re further away from the nucleus (less pull=less constraint)
ion
formed when atom gains or loses e’s
ionic radius: lose electrons
becomes smaller
e’s lost (possible empty orbital)
nucleus pulls remaining e’s closer
ionic radii trend: period (left to right)
positive ions decrease from groups 1-13
neg ions decrease from groups 14-17
ionic radii trend: groups
increases going down
ionization energy
energy needed to remove valence e
ionization energy trend in a period (left to right)
increases
elements on right want to gain e’s since they are closer to achieving the octet
stronger pull
ionization energy trend down a group
decreases
atomic radius increases
less pull
octet rule
atoms tend to gain, lose, or share e’s in order to get a full set of 8 valence e’s
electronegativity
ability to attract e’s in a chemical bond
types of ions
cation
anion
cation
positive (lost e)
metals
smaller than original atom
anion
negative, gain e
nonmetals
larger than original atom
shielding
e’s between nucleus and valence shell shield pull on valence e’s
ditomic elements
7, make a 7 in periodic table
always occur in pairs in nature (ex. N2, O2)
top of 7 starts at NOF
periodic law
there’s a periodic repetition of chemical and physical properties of elements when arranged by increasing atomic #
shielding effect trend: period
constant
shielding effect trend: group
increases from top to bottom
more energy levels
why are valence e’s not shielded from the increasing positive nuclear charge as atomic radius increases across a period?
no e’s (energy level n) come between the nucleus and valence e’s
second ionization energy
removing the 2nd e
requires more energy
why is the octet rule useful?
used for predicting what types of ions an element will form
Which block is He a part of?
s
Why do elements in the same group have similar chemical properties?
same # of valence e’s
valence e configuration
last part of normal e configuration
shows the # of valence e’s
determining # of valence e’s for representative elements
s and p block (count in)
