Strength  [ENDORSED]

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MichelleT_1L
Posts: 20
Joined: Fri Sep 29, 2017 7:04 am

Strength

Postby MichelleT_1L » Fri Dec 08, 2017 11:53 pm

What are the best ways to determine strengths of acids and bases when given the molecular formula?

Emily Glaser 1F
Posts: 156
Joined: Thu Jul 27, 2017 3:01 am

Re: Strength

Postby Emily Glaser 1F » Fri Dec 08, 2017 11:58 pm

1. If it's diatomic acid, strength is determined by size, so HCl has a weaker bond than HF since it's a larger atom, so HCl can dissociate better than HF.
2. If it's oxoacid, look at number of O atoms since more electrons are pulled away when there are more O atoms, so HClO3 weaker than HClO4
3. Same O, different element: examine electronegativity of central atom since more electronegative has stronger dipole moment on bond than others, so H will break off better

diangelosoriano
Posts: 49
Joined: Fri Sep 29, 2017 7:07 am

Re: Strength  [ENDORSED]

Postby diangelosoriano » Sat Dec 09, 2017 6:58 pm

Another method is to determine the stability of the conjugate base. If it is a very stable structure, the acid is strong. If the resulting conjugate base has an unstable structure, the acid was weak.

Justin Lai 1C
Posts: 50
Joined: Fri Sep 29, 2017 7:04 am

Re: Strength

Postby Justin Lai 1C » Sun Dec 10, 2017 9:02 pm

Stronger acids tend to have a greater percent ionization because its conjugate base will tend to stay in that form and be more stable.

Rummel Requerme 1E
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Joined: Fri Sep 25, 2015 3:00 am
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Re: Strength

Postby Rummel Requerme 1E » Sun Jun 10, 2018 6:10 pm

As stated above, the conjugate base is a good indicator: the more stable it is, the more strong the acid is.

MinyoungHong_1L
Posts: 12
Joined: Fri Apr 06, 2018 11:03 am

Re: Strength

Postby MinyoungHong_1L » Sun Jun 10, 2018 11:27 pm

So, generally speaking, the greater the electronegativity of whatever atom or molecule that the H+ is disassociating from, the stronger the acid due to the increased polarity/ionic character of that compound?


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