Elements in the same group of the periodic table often form oxyanions with the same general formula. The anions are also named in a similar fashion. Based on these observations, suggest a chemical formula or name, as appropriate, for each of the following ions: (a) BrO? , (b4?SeO? , (c) a3?enate ion, (d) hydrogen tellurate ion.
Solution : Here we have to write the name or chemical formula depending upon the ions given : Step 1: The ins given above are oxyanions. Let’s see what is an oxyanion And then look into the rules on naming oxyanion. An oxyanion or oxoanion is an anion that contains oxygen ion and it has generic formula A O y- x z where, A represents a chemical element O represents an oxygen atom. Step 2: Now, let’s see the rules to name the ion first and depending on that we will name or write the chemical formula for the ion : Oxyanions when combined with cations, forms four different kinds of oxyanions and they get a prefix along with their suffix. The first and lowest size ion gets hypo- as its prefix. The largest size ion gets per- as its p refix. hey are as follows : 1) Oxyanion with 1 oxygen atom but with same charge- root name of anion gets a prefix ‘hypo-’ and suffix ‘ -ite’. 2) Oxyanion with 2 oxygen atom but with same charge- root name of anion gets only suffix ‘-ite’ 3) Oxyanion with 3 oxygen atom but with same charge- root name of anion gets only suffix ‘-ate’ 4) Oxyanion with 4 oxygen atom but with same charge - root name of anion gets prefix ‘per-’ and suffix ‘ -ate’.