Page 1 of 1

HClO has pKa =7.53. How is it acid if its pH is >7

Posted: Sun Aug 21, 2011 12:07 pm
by Chem_Mod
HClO which has a pKa of 7.53. How is it an acid if its pH is greater than 7? Is it dependent on whether is a proton donor rather than the pH?

Re: HClO has pKa =7.53. How is it acid if its pH is >7

Posted: Sun Aug 21, 2011 12:07 pm
by Chem_Mod
You are confused between pH and pKa which are very different. pKa tells the degree of dissociation of an acid. pKa= -logKa and Ka = [H3O+]*[A-]/[HA]. The smaller the the pKa, the larger the Ka meaning the acid is strongly dissociated into H3O+. So indeed HClO is a strong acid compare to HBrO (pKa = 8.69). In order to determine the pH of a HClO solution, you need to know the concentration of H3O+ in that solution because pH = -log[H3O+].