Order these chemical species by increasing of an aqueous solution of each. That is, imagine making an solution of each species. Select next to the species that makes the solution with the lowest . Select next to the species that makes the solution with the next higher , 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 of pure water to the of the other solutions. Species Relative PH of 0.1M aqueous solution
HCOOH
CIO2^-
HCOO^-
H2O
H3PO4
H2PO4
H2PO4^-
H3O^-
HClO2

H3O^+ < HClO2 < H3PO4< HCOOH < H2PO4^-<CIO2^-<H2O< HCOO^-

Explanation:

The pH of a solution refers to the negative logarithm of it's hydrogen ion concentration. Generally, the hydrogen ion concentration of an acid is always greater than that of its conjugate base. Hence, the conjugate acid always has a lower pH than the conjugate base.

This can be seen in the species, H3O^+ and H2O, HClO2 and ClO2^- etc.

the answer is b because, investigating whether another species of moth also drinks tears might be interesting, but it would not directly explain why this species of moth does.

to explain why this species of moth drinks tears, the scientist could ask: "what nutrients that moths need are in elephant tears? "

the scientist could experiment with moth repellent or oter ways to keep the moths away, but that would not answer his original question.

c. electrical charges of ionic bonds.