GROUP 2
PHYSICAL PROPERTIES
Atomic Radius
Group 2 elements form +2 ions when they react.
Group 2 elements lose 2 electrons to form +2 ions. All group 2 metals have
electronic configurations that end in s2
Extra shells added as we go down group 2
Atomic radius increases as we go down group 2.
1st ionisation energy
1st ionisation energy decreases as you go down group 2.
Extra shells added as we go down group 2.
The outer electrons are also further from the nucleus which weakens the
attraction
There is more shielding hence weaker attraction between the nucleus and outer
electrons.
Both of these make it easier to remove the outer electron and so less energy is
needed to remove the electrons.
There isn't an increase in the number of protons as we go down the group.
However, the shielding effect overrides an increase in positive charge.
Melting points
Generally, decrease
Group 2 elements form metallic structures where you have positive metal ions
attracted to a delocalised negative sea of electrons
Larger ions mean the distance between the positive nuclei in metal ions and
delocalised electrons is greater. This weakens the attractive force.
GROUP 2 1
PHYSICAL PROPERTIES
Atomic Radius
Group 2 elements form +2 ions when they react.
Group 2 elements lose 2 electrons to form +2 ions. All group 2 metals have
electronic configurations that end in s2
Extra shells added as we go down group 2
Atomic radius increases as we go down group 2.
1st ionisation energy
1st ionisation energy decreases as you go down group 2.
Extra shells added as we go down group 2.
The outer electrons are also further from the nucleus which weakens the
attraction
There is more shielding hence weaker attraction between the nucleus and outer
electrons.
Both of these make it easier to remove the outer electron and so less energy is
needed to remove the electrons.
There isn't an increase in the number of protons as we go down the group.
However, the shielding effect overrides an increase in positive charge.
Melting points
Generally, decrease
Group 2 elements form metallic structures where you have positive metal ions
attracted to a delocalised negative sea of electrons
Larger ions mean the distance between the positive nuclei in metal ions and
delocalised electrons is greater. This weakens the attractive force.
GROUP 2 1
