What trends are shown as you go down group 2 of the periodic table?

Group 2 (the alkaline earth metals) show many different trends. As you go down, the size of the atoms increases. This is due to the fact that each element has an extra full main level of electrons compared to the one before it. Due to the size of the atoms increasing, the strength of the metallic bonds between atoms of the element decreases going down the group. This is because the sea of delocalised electrons is getting further away from the positive nuclei (due to the extra main level of electrons). This causes the melting point of the metals to reduce as you go down the group. For the same reason the first and second ionisation energies also decrease going down the group, the outer electrons are further away from the positive nuclei and there is more shielding of other electrons, therefore it is easier to remove the outer electrons.
In a reaction with water, the metals get more reactive as you go down the group. These tend to form hydroxides with the formula M(OH)2, however magnesium can also form magnesium oxide (MgO) in a reaction with steam (this occurs more rapidly than magnesium's reaction with cold water). The solubilites of the hydroxides formed increases going down the group, Mg(OH)2 is almost insoluble, whereas Ba(OH)2 dissolves in water readily. The opposite trend is true for the solublities of the sulphates, with general formula MSO4.