Periodicity Flashcards
Define First Ionisation Energy
Energy required to remove one electron from each atom in 1 mole of gaseous positive ions
What three factors increase ionisation energy
Electron Shielding
Atomic radii
Nuclear charge
What happens to ionisation energy across a period
Increases
Nuclear charge increases
Atomic radius decreases
Electron shielding stays the same
What happens to ionisation energy down a group
Decreases
Electron shielding increase
atomic radii increases
nuclear charge increases
What is a metallic bond
Strong electrostatic attraction between positive metal ions and negative delocalised electrons
Properties of Giant metallic latice
High m.p + b.p due to strong electrostatic forces
Insoluble due to strong electrostatic forces
Good conductors as delocalised electrons can move to carry charge
Properties of Giant Covalent Lattice
High m.p + b.p due to strong covalent bonds between atoms
Insoluble due to strong covalent bonds
Only graphene and graphite are conductive
What happens to the solubility of Hydroxides from group 2
Increases down the group
This means more OH- are present and thus more alkaline
What are the uses of group 2 bases
Ca(OH)2 is added to neutralise soil
Mg(OH)2 and Ca(OH)2 are used as antacids
What is the electron configuration of halogens
s2 p5
What is the trend in boiling point for halogens
Increases as you go down,
more electrons
more london dispersion forces
more energy needed
What is the trend in reactivity for halogens
Decreases
Electron shielding increases
Atomic radii increases
Nuclear charge increases
Less nuclear attraction
What colour does bromide form in an organic layer
orange
What colour does Iodine form in an organic layer
Purple
what is disproportionation
When an element has been both oxidised and reduced
