Order these chemical species by increasing $pH$ of an $0\mathrm{.}1M$ aqueous solution of each. That is$,$ imagine making an $0\mathrm{.}1M$ solution of each species. Select $1$ next

to the species that makes the solution with the lowest $pH.$ Select $2$ next to the species that makes the solution with the next higher $pH,$ and so on$.$

Notice that some of the rankings have been filled in for you already. Also notice that water is on the list. For that particular case, just compare the pH of pure

water to the $pH$ of the other solutions.

Note for advanced students: for all charged species, you may assume the necessary counterions act as neither acids nor bases.