Explore BrainMass

Finding pH from ion concentrations

Could you show me how you solved to get pH of each solution:

Solution A has [H3O+] = 7.2à?10-5
Solution B has [H3O+] = 7.2à?10-4
Solution C has [OH-] = 3.0à?10-11
Solution D has [OH-] = 6.5à?10-11

(i) Which solution has the highest pH?
(ii) Which solution is the least acidic?
(iii) Which solution is the most acidic?
(iv) Which solution has the lowest pH?

Solution Preview

According to Arrhenious concept, an acid is defined as a substance that dissociates in water to give H+ (or H3O+) ions.
<br>for example,
<br>HCl + H2O -> H3O+ + Cl-
<br>A base is a substance that contains OH- ions or dissolves in water to produce OH- ions.
<br>For example,
<br>NH3 + H2O -> NH4+ + OH-
<br>The strength of an acid is a measure of the H+ ion ...

Solution Summary

The solution gives not only the answers but also the steps required to arrive at the answer. No mathematical step was avoided in the derivation.