periodicity Flashcards
Why does xenon have a lower first ionisation energy than neon
Xe has bigger atomic radius and more shielding
Nuclear attraction decreases
Suggest reasons for the difference between the enthalpy changes of solution of KF and RbF
potassium ion is smaller
lattice enthalpy of KF is more negative than RbF (meaning K+ has greater attraction for F-)
enthalpy of hydration of K+ is more negative than Rb+ (meaning K+ has greater attraction for water)
enthalpy of solution affected more by lattice enthalpy than enthalpy of hydration
Bromine structure and bonding
simple molecular
induced dipole dipole forces/London forces between molecules
does not conduct electricity as no mobile charge carriers
why is it in s block
highest energy electron is in s subshell / s orbital
SiO2 structure
giant covalent lattice
CO2 structure
simple molecular lattice
octahedral shape
sf6
non metals + water
acids/acidic oxides
metals + water
alkaline/basic solutions
why does magnesium have higher melting point than sodium
magnesium has more outer electrons
magnesium ions have greater charge
magneisum has greater attraction between ions and delocalised electrons
metallic bonding definiton
electrostatic attraction between positive ions and delocalised electrons
covalent bonding definition
attraction between a shared pair of
electrons and the nuclei of the (bonded) atoms
State how and explain why the attraction between nuclei and outermost electrons in gaseous
atoms varies across Period 3.
The attraction (between nuclei and outermost
electrons) increases
AND
The nuclear charge increases
electrons experience similar shielding
OR
Same number of shells
Atomic radius decreases
why don’t ionic conduct when solid
ions are fixed in ionic lattice
why does S8 have higher melting point than P4
larger molecules so greater London forces
higher melting point
when there’s more ionisations, why does successive ionisation increase
radius decreases
AND
attraction between electrons and
nucleus increases
Explain how the successive ionisation energies provide evidence for the
electron shells in atoms
large difference shows a different shell
Explain how the first ionisation energies of magnesium and aluminium give further
details of electron structure
Mg has (outer) electron in (3)s sub-shell
AND
Al has (outer) electron in (3)p sub-shell
(3)p sub-shell has higher energy than (3)s sub-shell so electrons in 3p are slightly easier to remove
when is the other big ionisation jump?
when gong from 2nd shell to the inner one. e.g. 1s2 2s2 2p4
big jump between 6th and 7th because i’m counting the powers from the back util i reach 1
trigonal planar structure
bf3
less shielding means
smaller
first ionisation energy definition
Energy change when each atom in 1 mole
of gaseous atoms
loses an electron
what forms tetrahedral molecules with hydrogen
carbon/silicon
