HW 12.51 part d
When you compare acids like HClO4 and H3PO4 that differ in multiple ways (number of H atoms, Cl v. P), how do you determine which one is stronger?
Acid strength-HClO4 vs H3PO4 (HW 12.51d)
Moderators: Chem_Mod, Chem_Admin
-
- Posts: 37
- Joined: Fri Sep 25, 2015 3:00 am
Re: Acid strength-HClO4 vs H3PO4 (HW 12.51d)
In this case, I think you just have to know that perchloric acid is a strong acid so it dissociates completely in an aqueous solution while phosporic acid simply does not as it is a weak acid. Sorry if I can't come up with a better explanation but I think this one of those more black and white answers where you just have to memorize the list of strong acids!
Hope I helped!
Hope I helped!
-
- Posts: 23858
- Joined: Thu Aug 04, 2011 1:53 pm
- Has upvoted: 1253 times
Re: Acid strength-HClO4 vs H3PO4 (HW 12.51d)
To approach this problem, we should look at the similarities of the polyatomic ions: there is one central atom (phosphorus/chlorine) and 4 surrounding oxygen atoms to which hydrogen atoms will attach. Chlorine has a higher electronegativity than phosphorus, so it pulls the oxygen atom electrons towards itself with greater force than phosphorus. The fact that chlorine has a higher pull means that oxygen electrons become less accessible for the hydrogen atoms to "share", making it less favorable for hydrogen to stay bonded versus dissociating from the acid. Phosphorus by contrast pulls the electrons less, meaning that hydrogen has greater access to oxygen electrons, making it less favorable for it to dissociate, hence why H3PO4 is a weaker acid.
Return to “Properties & Structures of Inorganic & Organic Acids”
Who is online
Users browsing this forum: No registered users and 10 guests