Determining strong/weak acids/bases
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Determining strong/weak acids/bases
Is there a way to determine if an acid/base is strong or weak by just looking at its formula? do we have to memorize all?
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Re: Determining strong/weak acids/bases
Hi! Rather than memorizing the molecules themselves, I would memorize the patterns. There are some acronyms and tricks to help remember too, I would recommend watching a Youtube video. Hope this helps!
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Re: Determining strong/weak acids/bases
Hi! One of the TAs taught this trick to determine whether if certain acids (H2S04, HNO3, HCl03) are strong or not. You would add 2 to the H and compare with the O. If H is equal to or greater than H, then the acid is strong. For example using H2S04, add 2 to the H would give H=4 and 0=4, this would make H2S04 a strong acid. However, I still feel like it would be better to just memorize the strong acids. For strong bases they occupy the first and second column of the periodic table. I hope this helps!
Re: Determining strong/weak acids/bases
I would also note that if the problem gives a Ka or Kb value, then you know the acid/base must be weak since strong acids and bases do not have these values.
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Re: Determining strong/weak acids/bases
Hey! To be honest, I just tried memorizing the strong acids and bases first and then assumed that any other acid or base would be weak!
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Re: Determining strong/weak acids/bases
It would be helpful to memorize the strong acids/bases since it will help you determine that everything else that isn't it is a weak acid/base. For strong acids, there are 7 acids to memorize and for the strong bases, it is everything with a cation from group 1 or 2. Hope this helps
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Re: Determining strong/weak acids/bases
A few trends that I found helpful for memorizing is that many inorganic acids are strong while many organic acids are weak, and many strong bases are metal hydroxides and metal oxides while many weak bases have a N atom with a lone pair. Hope this helps!
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Re: Determining strong/weak acids/bases
A good trick to memorizing strong bases is by knowing that if the equation has an OH- and a cation from either group 1 or 2, it should be a strong base. For the strong acids, I memorized them by learning to say them out loud, phonetically.
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