The value given is called the Avogadro's number. It is the number of particles in every 1 mole of any substance. I think this is a trial and error process. Input 6.022x10^23 into your calculator. Add to this a number consisting of the maximum digit which is 9. Apparently, when 10×10¹³ is added, the display already changes. Therefore, the largest number would have to be 10×10¹².
There is a rule in naming polyatomic anions containing oxygen.
Those names ending in <em>–ate</em> are given to the most common oxyanion of an element.
While those names ending in <em>–ite</em> are for those that contains fewer O atom for
the same charge. Since P has fewer O atoms, its name ends in <em>–ite</em>.
Thus, P is phosphite while P is phosphate.