inorganic Flashcards
(136 cards)
trend in boiling points of METALS
in period three + reasons
increases
higher atomic charge
smaller atoms
more protons
more delocalised electrons per atoms
more energy to overcome
silicone melting point
high melting point
giant covalent lattice
very strong covalent bonds
phosphorous, sulphur, chlorine melting points
low melting points
weak van der waals forces
S>P>Cl, bigger molecules = more electrons = more van der waals
argon melting points
very low melting point
monatomic
very weak van der waals
reasons for atomic radius decreasing across period
more electrons and protons
same shell
equal shielding
greater attraction
reason electronegativity increases across a period
smaller radius
more protons
more attraction between nucleus and two bonding electrons in covalent bond
general change in ionisation energy across period 3
increases
more electrons and protons
no more shielding
greater attraction
more energy to overcome
reason for dip in ionisation energy from Mg to Al
Mg loses from 3s orbital
Al loses from 3p orbital
3p has higher energy than 3s
reason for dip in ionisation energy from P to S
P loses electron from orbital with one electron
S loses electron from orbital with two electrons
electron-electron repulsion in S
general trend in melting point of period three oxides
decreases
trend + reasons for melting point of first three period 3 oxides (ionic)
high (ionic structure)
MgO and Al2O3 highest due to higher charges making attraction stronger
reason for melting point of SiO2
giant covalent structure = high melting point
strong covalent bonds
macromolecular
trend and reasons for melting points of P4O10 and SO2
low (only van der waals forces)
simple covalent molecular structure
P4O10 higher due to being a larger molecule
equation for formation of sodium oxide
4Na + O2 -> 2Na2O
equation for formation of magnesium oxide
2Mg + O2 -> 2MgO
equation for formation of aluminium oxide
4Al + 3O2 -> 2Al2O3
equation for formation of silicon oxide
Si + O2 -> SiO2
equation for formation of phosphorus oxide
P4 + 5O2 -> P4O10
equation for formation of sulphur oxide (oxidation state of 5)
S + O2 -> SO2
equation for formation of sulphur oxide (equilibrium)
SO2 + O2 <-> SO3
reaction of basic oxides with water explanation
ions dissolve (some partially) and O2- (from compund) reacts with water
O2- + H2O -> 2OH-
reaction of sodium oxide with water
Na2O + H2O -> 2NaOH
reaction of magnesium oxide with water
MgO + H2O -> Mg(oh)2
why is aluminium oxide insoluble
high lattice enthalpy