Properties of Period 3 elements and their oxides Flashcards
how do Na and Mg react?
both react ionically to form positive ions
which is more reactive, Na or Mg, and why?
Na is more reactive than Mg because it only has to lose one electron (whereas Mg has to lose two) so less energy is required to ionise it
what do the period 3 elements react with oxygen to form?
oxides in their highest oxidation state
what are the oxides that form form the period 3 elements:
- phosphorus
- aluminium
P4O10
Al2O3
what is required for sulfur trioxide (SO3) to form?
high temperatures and a catalyst
what affects the reactivity and melting points of the period 3 oxides?
structure and bonding
the reaction of Mg with water
Mg + 2H20 –> Mg(OH)2 + H2
the reaction of Mg with steam
Mg + H20 –> MgO + H2
how does Mg react with water?
very slowly
how does Mg react with steam?
vigorously, burning with a bright white flame
how does Na react with cold water?
vigorously, with lots of fizzing
how do the period 3 elements react in air?
Na, Mg, P and S react readily
Al and Si react slowly
what are Na2O, MgO and Al2O3?
ionic oxides (metal + non-metal)
why does MgO have a higher melting point than Na2O?
the Mg2+ ions are more strongly attracted to the oxygen than the Na+ ions
why do P4O10 and SO2 have low melting points?
they form simple molecular structures held together by VDWs and dipole-dipole forces (weak IMFs)