Tricks for identifying Strong/Weak Acids & Bases

Moderators: Chem_Mod, Chem_Admin

Lauren Ho 2E
Posts: 70
Joined: Tue Oct 09, 2018 12:16 am

Tricks for identifying Strong/Weak Acids & Bases

Postby Lauren Ho 2E » Thu Jan 24, 2019 4:05 pm

Does anyone know of any tips or tricks that will allow you immediately to identify an acid or base as weak or strong?

Kate Chow 4H
Posts: 61
Joined: Fri Sep 28, 2018 12:28 am

Re: Tricks for identifying Strong/Weak Acids & Bases

Postby Kate Chow 4H » Thu Jan 24, 2019 4:10 pm

If you know Ka or Kb, you can determine the strength of an acid or base. But if you don't, there's a short list that you can memorize or know pretty well. For example, most all of the strong bases use the elements in the first 2 columns of the periodic table.

mbaker4E
Posts: 69
Joined: Fri Sep 28, 2018 12:26 am

Re: Tricks for identifying Strong/Weak Acids & Bases

Postby mbaker4E » Thu Jan 24, 2019 4:20 pm

These are some general strong acids/bases I memorized:
Strong Acids - HCl, HBr, HI, HNO3, HClO3, HClO4, H2SO4
Strong Bases - LiOH, NaOH, KOH, RbOH, CsOH, Ca(OH)2, Ba(OH)2, Sr(OH)2

Casandra
Posts: 65
Joined: Fri Sep 28, 2018 12:17 am

Re: Tricks for identifying Strong/Weak Acids & Bases

Postby Casandra » Thu Jan 24, 2019 4:21 pm

Lauren Ho 2E wrote:Does anyone know of any tips or tricks that will allow you immediately to identify an acid or base as weak or strong?

For strong bases and strong acids, it would help to memorize the list of strong acids and bases, because then you know anything that is not a strong base or acid, has to be weak. Also side note, for the most part any base that does not gave OH is weak

Sarah_Kang_2K
Posts: 72
Joined: Fri Sep 28, 2018 12:23 am

Re: Tricks for identifying Strong/Weak Acids & Bases

Postby Sarah_Kang_2K » Thu Jan 24, 2019 4:44 pm

For Test 1, what should we know about the pH of weak acids and weak bases and its salt? We didn't go over this in discussion. Do we just need to know how to calculate it?

Ethan Baurle 1A
Posts: 33
Joined: Fri Sep 28, 2018 12:19 am

Re: Tricks for identifying Strong/Weak Acids & Bases

Postby Ethan Baurle 1A » Thu Jan 24, 2019 4:45 pm

Anytime we are given a Ka or Kb, the acid or base is almost certainly going to be weak. This is because the Ka or Kb of a strong acid or base is extremely high because the substance gets basically completely deprotonated/protonated. This should help you in identifying weak substances right away, and then you can either memorize strong ones or the problem may indicate it is a strong substance in some way.


Return to “Equilibrium Constants & Calculating Concentrations”

Who is online

Users browsing this forum: No registered users and 2 guests