perodic classification Flashcards
s block electronic config
ns^1-2
group 1 elements are known as
alkali elements
group 2 are knows as
alkaline earth elements
p-block config
ns^2np^1-6
elements who show diagonal relationship
li with mg , be with al, b with si
d-block config
(n-1)d^1-10ns^0-2
IONIC radius
ionic radii>neutral atom , radii directly propotional negative charge,
what is ionization enthalpy
enegry required to remove an outermost electron from an ground atom to form cation
trend in ionization enthalpy
IE increases left to right and decreases down the group,but half & fully filled orbitals are more stable ho high IE, IE inversly to atomic size ,charge directly to IE,
IE1 of group 2 element > of grp 13
what is electron enthalpy
energy released when an electron is added to an atom
trend in electron gain enthalpy
EGE increses left to right, and decreases down the group, it is inversly to atomic size , directly to nuclear charge , half and fully filled EGE will be less
what is electronegativity
tendecy of an atom to attaract shared pair of electron towards itself, only depend upon nuclear charge or size
trend in electonegativity
left to right increases, down the group decreases
flourine is the most electronegative element
metallic character
will decrease from left to right
increases down the group
chemical reactivity for metals
invesely to IE,EN directly to atomic radii
reactivity for non-metals
directly to EN,ege and inversely to atomic radii
trend of chemical reactivity
down the group ,metals reactivity increases and non metal decreases , across the group metals reactivity decreases, non metal increases
reducing character
increase down the group,decrease across period
oxidizing character
decrease down the group, increases across the priod
oxides
M+02—->MxOy
non-metals
Hydrogen (sometimes) Carbon. Nitrogen. Oxygen. Phosphorus. Sulfur. Selenium. Fluorine bromine iodine
acidic
the oxide which form acid on hydrolysis
usually non-metals oxides are acidic in nature
basic
the oxide which form base on hydrolysis
usually metal oxides form base
amphoteric
the oxide which doesn’t react with H2O but can react with both acid and base
eg:Al203
neutral
this oxide doesn’t react with anything
C0(carbon monooxide)
NO(nitric acid)
ionization potential
it is the minimum amount of energy required to remove an outermost loosely held electron from isolated gaseous atom
successive IP
when any element remove more than 1 electron , nucleus increases charge to hold remaining electron
so the successive IP gets exceptionally high
successive IP∝ energy required
no of electron ∝ 1/z-eff
most stable electron configuration
ns^2np^6–> noble gas config.
factors affecting IP
1. atomic size or atomic radii
down the group ∝ no of shell increases IP∝1/no. of shell IP DECREASES DOWN THE GROUP across the period ∝no of electron electron increases ∝1/size IP INCREASES ACROSS THE PERIOD
factors affecting IP
nuclear charge
down the group ∝ 1/nuclear charge
across the period ∝ nuclear charge
factors affecting IP
penetration power
highest penetration power or IP required to remove electron is s>p>d>f
factors affecting IP
electronic configuration
half-filled and fully filled orbital are exceptionally stable. Due to symmetric distribution
exception of IP
shielding and screening effect
IP of 4th period > IP of 3rd period
electron gain enthalpy
it is the minimum amount of energy required or released when an electron is added
negative means energy is released
positive means energy is absorbed
this concept of electron gain is mostly applicable for non metals bcoz they have a tendency to accept electrons
second electron gain
it is always positive ,because repulsion increases after 1st electron
factors affecting electron gain enthalpy
atomic size
down the group electron gain enthalpy decreases
across the periods increases
halogens have the highest value of electron gain enthalpy
electropositivity
tendency to lose electron and attain positive ion
a more electropositive character means more metallic character
ACROSS THE PERIOD DECREASES
DOWN THE GROUP INCREASES
analomous behavior
every 1st element of the every group is different from rest of the group smallest size highest IP highest value of EGE highest electronegativity
alkali metals
most reactive ,strongest reducing agent and have lowest IP
halogens
most reactive ,strongest oxidizing agent anf have high IP
Size of species
Size of species inversely proportional to nuclear charge
Exception in electron gain enthalpy
In group 17 , cl > F because of F small size
