Definitions
What definition is this?
The smallest unit of an element that retains it's chemical properties.
Atom
The atomic radius decreases when going down a group.
False.
Increases
What does electron configuration count?
Number of electrons in a atom
O is
Oxygen
Ends with S^1
Alkali Metals
Define periodic table
A table of the chemical elements arranged in order of atomic number.
Nuclear charge x from up to down in a group
x= increases
Write Lithium's electron configuration
1s^2, 2s^1
Potassium is
P ( True or false)
False. K
Group 17
halogens
Define atomic number.
Number of protons in an atom's nucleus.
Electronegativity x from right to left on the same period.
In noble gas notation. Which one is correct?
[Rn], [K], [H], [Na], [F]
[Rn]
Na
Sodium
Belongs to the D block
Transition metals
The energy required to remove a valence electron from an atom's outermost shell refers to
Ionization energy
Ionization energy x from left to right on the same period.
x= increases
What comes next
1s^2, 2s^2, 2p^6, 3s^2, 3p^6,
4s^2
Element with most electro-negativitey
Fluorine
Most reactive family.
Alkali metals
Define average atomic mass.
The average mass of all an elemt's isotopes.
Why does an atom's atomic radius decrease when going left to right on the same period.
Same period = same number of energy levels = same shielding effect.
Since an atom's nuclear charge increases when going left to right, the valence electrons are more attracted to the nucleus. Which decreases atomic radius.
Determine an atom's location on the periodic table from its electron configuration.
1s^2, 2s^2, 2p^6, 3s^2, 3p^6, 4s^2, 3d^10, 4p6
It has 4 energy levels, so it resides on period 4.
ends in 4p^6, so it resides on the p block. (group 13-18).
It ends with p^6, so it is the 6th group, so group 18.
Period 4, group 18.
Hg is
Mercury
Group with a full outer shell.
Noble gasses