module 3 Flashcards
define the first ionisation energy
energy required to remove one electron from each atom in one mole of gaseous atoms of an element
what electron will experience least nuclear attraction
highest energy level
how does atomic radius affect the ionisation energy
F of attraction falls off sharply with increasing distance
how does nuclear charge affect the ionisation energy
more protons in the nucleus, the greater the nuclear attraction of the outermost electron
how does electron shielding affect the ionisation energy
inner-shell e- repel outer-shell e-(shielding effect) which reduces the nuclear attraction of the outer electrons
how does an unpaired electron increase the ionisation energy
single electron pulled closer to the nucleus so the nuclear attraction increases so the ionisation energy increases
what is the trend in ionisation energy across the period
increase
what is the trend in ionisation energy for periods at the end of the table and periods at the start
sharp decrease
what is the trend in ionisation energy down the group
decrease
explain the trend in first IE down the group
atomic radius increases
shielding increases
outweighs the effect of the nuclear charge
so nuclear attraction decreases
so first IE decreases
explain the trend in first IE across a period
nuclear charge increases
(similar shielding)
nuclear attraction increases
atomic radius decreases
first IE increases
explain the lower IE of oxygen compared to nitrogen
outer electrons in same sub-shell
oxygen has a paired e- , the e- repel each other making it easier to remove
therefore, the IE of oxygen is less
outline the properties of metals
strong metallic bonds
high electrical conductivity
high melting & boiling point
what does the melting point of a metal depend upon
the strength of the metallic bonds
do metals dissolve
no
outline the melting&boiling points, the solubility and electrical conductivity of giant covalent structures
high melting & boiling points
insoluble
non-conductor of electricity (except graphene)