Telling Apart Weak Bases vs Weak Acids by their Formula

[Rayna Irving 2C]

Can you guys name some ways to tell if a compound is a weak acid or a weak base just by looking at the formula when trying to calculate equilibrium concentrations, I've been having some trouble with that.

[705340227]

I have been having trouble with this as well. One thing that I do know is if something is negative, it’s most likely going to be a base. If something is positive, it’s most likely going to be an acid. Hope that helps a little!

[Amanda Bueno-Kling]

I think the best strategy is to memorize strong acids and bases, and consider all others as weak. I'm not sure what tips there are other than: I know most acids with COOH (carboxyl group) in them are generally weak acids, like acetic acid for example.

[Charlotte Chen 3B]

There's a link Dr. Lavelle shared previously with a table of the strong acids and bases to know:

https://sites.google.com/site/chempendi ... cids-bases

I think for the purposes of this course and as stated on the table, you can assume any other acids/bases not on the table are weak!

[Kaihan_Danesh_2J]

Weak Bases are bases that are not listed in the strong bases list and weak acids are acids not listed in the strong acids list. If you are referring to whether something is an acid or base specifically, then you can usually tell based on their 1.) lewis structure or 2.) their charge. In the case of salts, you must look at the individual components of the salt to determine whether it's acidic or basic. If the basic component is usually part of a strong base, then that basic component is a weak base. Same goes for the acid component. However, if the conjugates of those components make a weak acid/base typically, then it can be said that that component is a strong acid/base.

[EnricoArambulo3H]

I would memorize the strong acids and bases and then assume all others are weak.

Strong acids: HCl04, HCl, H2SO4, HBr, HI, HNO3, and some say HClO3
Strong bases: Group 1 Hydroxides, Calcium, Barium, and Strontium Hydroxides

I hope this helped!

[Kathy_Li_1H]

Hi! For me, I find that using flash cards to memorize the strong acids and bases is the best way to easily identify strong/weak acids and bases. Since there are a lot less strong acids and bases than their weak counterparts, I would just suggest knowing the strong acids and bases.

Strong Acids: HCl, HBr, HI, HClO3, HClO4, HNO3, H2SO4
Strong Bases: Group 1 hydroxides, Ca(OH)2, Sr(OH)2, Ba(OH)2, Group 1 and 2 oxides

[Bai Rong Lin 2K]

I would just memorize the strong acid and bases and that helps a lot.

[Joshua_Chan_3K]

There really isn't a way as far as I know. I searched it up as well and it doesn't seem like you can figure it out just based on the formula. I would follow everyone else's recommendation and just memorize the strong ones, the rest will be weak. There's not that many so its really not that much work. In terms of conjugates just know that if its weak, the conjugate is weak and if its strong, the conjugate is so weak its neutral.

[Katelynn Shaheen 2C]

Knowing the strong acids and bases will help you find out which ones are weak.

Strong Acids:
HCl
HBr
HI
H2SO4
HNO3
HClO4
HClO3

Strong Bases:
LiOH
NaOH
KOH
RbOH
CsOH
Ca(OH)2
Sr(OH)2
Ba(OH)2

[Michelle Nguyen 3F]

The best thing would be to memorize all of the strong acids and strong bases (roughly there 6-8 strong bases and 7 strong acids). Consider anything that is not among the list of strong acids and strong bases as weak acids and bases.

[Nan_Guan_1L]

I think the best solution to that is by being clear of the list of strong acid/ bases. You can find the list in sapling solutions and also in the textbook. Basically everything beside those would be considered a weak acid / base.