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Xishan
Jun13-05, 10:11 PM
I've posted this question in another thread... didn't get the answer though

Why does a strong acid (or a base) ionizes to a higher extent? Is this extent of ionization the only criteria for characterizing an acid (or a base) as strong or weak. Is it the simple bond polarization phenomenon that causes the ionization?

undertow
Jun13-05, 11:06 PM
i'm not a tutor but i would guess its due to bond strength. probably wrong tho

Loren Booda
Jun13-05, 11:17 PM
Does hydrogen bonding have some effect on pH?

Bladibla
Jun14-05, 03:46 AM
Its due to the 'regularity' of the acid molecule to dissociate into Oxonium ions. For example, Hydrogen fluride has only something like 10% - 20% of its molecules dissociating into oxonium ions, while a 'strong' acid such as hydrochloric acid will have 90 - 100% dissocition of its molecules into oxonium ions.

Xishan
Jun15-05, 10:46 AM
So, my question stands unanswered! Why does HCl dissociate to such a high extent and while HF to only a little extent???

Bladibla
Jun15-05, 11:20 AM
So, my question stands unanswered! Why does HCl dissociate to such a high extent and while HF to only a little extent???

Its because the H-F Bond is much stronger than the H-Cl bond.

Note: you asked why strong acids IONIZE to a higher extent, and technically, this has been answered.

redwraith94
Jun15-05, 04:31 PM
It is due primarily to bond strength, and temp...water only has the ability to pull apart some acids, that is one reason why 'sensitive' reactions take place @ lower temps. The acids dissassociate less because the water only has a certain amount of strength to rip them apart in the first place.

Xishan
Jun16-05, 01:02 AM
Its due to the 'regularity' of the acid molecule to dissociate into Oxonium ions. For example, Hydrogen fluride has only something like 10% - 20% of its molecules dissociating into oxonium ions, while a 'strong' acid such as hydrochloric acid will have 90 - 100% dissocition of its molecules into oxonium ions.

Hmmm... OK! I admit, Bladibla, you are right. You've answered my question. I actually overlooked the first sentence of your reply. Thanks!

Can someone please name around ten strong acids, strong bases, weak acids and weak bases and give their respective %ionization?

Xishan
Jun16-05, 10:55 AM
I got it myself, not TEN though!

http://www.dbhs.wvusd.k12.ca.us/webdocs/AcidBase/Strong-Weak-AcidBase.html
http://www.members.aol.com/profchm/tcjc_ch15.html

I'll be back with more questions in future. Inshallah