Write the formula and name of the compound formed from the following ionic interactions; 

(a) The 2+ ion and the 1-ion are both isoelectronic with the atoms of a chemically unreactive Period 4 element, 

(b) The 2+ ion and the 2? ion are both isoelectronic with the Period 3 noble gas. 

(c) The 2+ ion is the smallest with a filled d subshell; the anion forms from the smallest halogen, 

(d) The ions form from the largest and smallest ionizable atoms in Period 2.