Strong vs. Weak Acids

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Janice Park 1E
Posts: 36
Joined: Fri Sep 28, 2018 12:22 am

Strong vs. Weak Acids

Postby Janice Park 1E » Thu Jan 24, 2019 5:09 pm

Just as a clarification, if the concentration of H3O+ is greater than 10^-3, or the pH is less than 3, then it is considered a strong acid?
Alternatively, if the concentration of OH- is greater than 10^-3, or the pOH is less than 3, then it is considered a strong base?

Brian Chhoy 4I
Posts: 66
Joined: Fri Sep 28, 2018 12:16 am

Re: Strong vs. Weak Acids

Postby Brian Chhoy 4I » Thu Jan 24, 2019 5:15 pm

Im not to sure about the exact concentration of hydronium or hydroxide, but strong acids/bases have pKa/pKb values that are greater than 10^3, and at that amount you can be sure that they fully dissociate.

Philip Lee 1L
Posts: 30
Joined: Fri Sep 28, 2018 12:21 am

Re: Strong vs. Weak Acids

Postby Philip Lee 1L » Thu Jan 24, 2019 5:17 pm

Instead of looking at concentrations, I think you need to look at equilibrium constants to determine whether or not an acid or base is considered strong/weak. For example, any acid with a Ka > 103 is considered to be a strong acid. For bases, you need to consider Kb values.

Celine Cheng 1H
Posts: 33
Joined: Fri Sep 28, 2018 12:21 am
Been upvoted: 1 time

Re: Strong vs. Weak Acids

Postby Celine Cheng 1H » Thu Jan 24, 2019 8:57 pm

Also, there are lists of common strong acids/bases that you can find online!
Here's one that I really like: http://www.chemistry.pomona.edu/chemist ... dbaset.htm


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