Group 2 metals Flashcards
what is the trend of atomic radius as you go down group 2 elements?
atomic radius generally decreases as you go down.
explain why atomic radius decreases as you go down group 2 metals?
each element has one more completer shell so the outer electrons are more further away from the nucleus.
what are the trend of first ionisation energy as you go down group 2?
first ionisation energy decreases down a group.
explain why first ionisation energy decreases as you go down group 2?
the increased distance and shielding from the nucleus outweighs the nuclear charge so it is easier to remove an electron
what are the trends of melting point as you go down group 2?
melting point decreases as you go down a group.
why does melting point decrease as you go down group 2?
the size of the cations increases so grater distance between the nuclei and the delocalised electrons so weaker metallic bonding.
What is magnesium used for?
to extract titanium
why is carbon not used to extract titanium?
c(s)+TiO2 (s)—> TiC(s)+ O2(g)
TiC is solid and brittle
equation for extraction of titanium
TiO2+2Cl2+2C–>TiCl4+2CO
TiCl4+2Mg–> Ti+2MgCl4
What is calcium used for?
Prevents acid rain.
how is acid rain formed?
2SO2+O2(g)—>2SO3(g)
SO3(g)+H2O(l)—>H2SO4(aq)
Equation for preventing acid rain?
CaO (s) +SO2 (g) —> CaSO3 (s)
(quicklime)
Alternative equations:
CaCO3(s)+SO2(g)—> CaSO3(s) + CO2 (g)
What is the trend of reactivity with water for group 2 metals?
Down a group the metals react more vigorously.this is because the ionisation energy is low, so easier to remove electrons and requires a lower activation energy.
Ca(s) + 2H2O(l)—>Ca(OH)2(aq)+H2(g)
Does magnesium react with water?
It’s hardly solvable but reacts with steam
What is the reaction of magnesium with steam?
Mg(s)+H2O(g)—>MgO(s)+ H2(g)
This produces a bright light
