Section 1 Flashcards
First ionisation energy
energy needed to remove 1 mole of electrons from 1 mole of gaseous atoms
The lower the ionisation energy the ____
easier to form an ion
Ionisation energy
nuclear charge
The more protons in the nucleus, the more positive charge there is and the stronger the attraction for the electrons
Ionisation energy
Atomic radius
An electron closer will be more strongly attracted
Ionisation energy
shielding
The more shielding, the less attraction between outer shell electrons and nucleus
Ionisation energy down the group trend
gets smaller because as you go down there are more shells that increases atomic radius and increases shielding
Ionisation energy across a period
get larger because there are more protons, higher nuclear charge and small radius
Ionisation energy across period
sometimes vary why?
due to electrons being in different types of orbitals
Second ionisation energy
energy needed to remove 1 electron from each ion in 1 mole of gaseous +1 ions to form 1 mole of gaseous 2+ ions
graphite structure
flat hexagons covalently bonded with three bonds
Graphite structure properties
weak forces between layers - sheets can slide
delocalised electrons allow current to flow
insoluble in any solvent - bonds to hard to break
high melting point
low density
diamond properties due to structure
high melting point
very hard
wont dissolve in solvent
cant conduct electricity
graphene properties
very strong
conducts electricity
transparent and light
metallic bonding
mp and bp
the more electrons the stronger the bonds so the higher the mp and bp
metallic bonding
ability to be shaped
no ions holding bonds together so ions can slide over each other
metallic bonding
conductivity
good thermal conductors
metallic bonding
solubility
insoluble because
metals across a period
bp and mp increase across period because ions have greater charge
increasing number of delocalised electrons
higher charge density
simple molecular structures
mp and bp
weak induced dipole-dipole forces
Group 2
As you go down group 2 __________- decreases and ___________ increases
ionisation energy
reactivity
Group 2
reaction with water
metal hydroxide and hydrogen
Group 2
Be reaction with water
doesn’t react
Group 2
reaction with oxygen
solid white oxides
Group 2
oxide exception
Magnesium
slow reaction - hydroxide insoluble
hydroxides are more soluble down the group so solution gets more alkali
