Strong/weak acids & bases

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Fdonovan 3D
Posts: 101
Joined: Sat Aug 17, 2019 12:16 am

Strong/weak acids & bases

Postby Fdonovan 3D » Thu Jan 23, 2020 2:48 pm

Are we going to have to know whether an acid or base is strong or weak just by its name or chemical formula? If so, how do we do know?

Brittney Hun 2C
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Joined: Wed Sep 11, 2019 12:15 am

Re: Strong/weak acids & bases

Postby Brittney Hun 2C » Thu Jan 23, 2020 2:52 pm

You would just have to memorize the six strong acids H2SO4 Sulfuric Acid, HCl Hydrochloric Acid, HBr Hydrobromic Acid, HI Hydroiodic Acid, HNO3 Nitric Acid, HClO4 Perchloric Acid. Everything else is considered a weak acid. Strong bases have a group 1 or 2 metal attached to a hydroxide (OH-). Everything else is considered a weak base.

Justin Seok 2A
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Joined: Sat Aug 24, 2019 12:15 am

Re: Strong/weak acids & bases

Postby Justin Seok 2A » Thu Jan 23, 2020 3:00 pm

For the most part, in this section, we mostly work with weak acids and such since they are best suited for equilibrium type problems. However, it would probably be good to have a general idea of common strong acids just so you won't get blindsided if they come up on the test. However, it shouldn't be something that is very likely to come up on the test.

Kristina Rizo 2K
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Re: Strong/weak acids & bases

Postby Kristina Rizo 2K » Thu Jan 23, 2020 5:53 pm

There is also a chart on page F75 in the seventh edition. It is in Fundamentals J, the table is Table J.1.

CameronDis2K
Posts: 51
Joined: Wed Feb 20, 2019 12:18 am

Re: Strong/weak acids & bases

Postby CameronDis2K » Thu Jan 30, 2020 5:26 pm

Yes, there's usually a pattern you can follow: anything with an OH- is usually a strong base (ex. KOH), and any compound preceded with an H and from the halogen group is usually a strong acid (HBr, HCl, etc.). But any compound with an NH3 is usually a weak acid, and others you can just memorize, like the weak acetic acid: CH3COOH.

Manav Govil 1B
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Joined: Sat Sep 07, 2019 12:19 am

Re: Strong/weak acids & bases

Postby Manav Govil 1B » Fri Jan 31, 2020 9:12 pm

You should be able to tell if something is a weak acid or base, based on if it can accept a proton or not. Also, you should have the strong acids memorized.

Sanjana Borle 2K
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Re: Strong/weak acids & bases

Postby Sanjana Borle 2K » Fri Jan 31, 2020 9:14 pm

Strong acids are usually ones that give off protons easily, such as HF or HCl. Strong bases will give off OH- easily, such as NaOH.

Pablo 1K
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Joined: Sat Feb 02, 2019 12:15 am

Re: Strong/weak acids & bases

Postby Pablo 1K » Fri Jan 31, 2020 9:41 pm

Just focus on recognizing the strong acids and bases and I believe the weak ones will become noticeable easier.

Catherine Daye 1L
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Joined: Wed Sep 11, 2019 12:16 am

Re: Strong/weak acids & bases

Postby Catherine Daye 1L » Sat Feb 01, 2020 3:08 pm

Yes, the best way is to memorize the strong acids and bases (there aren’t too many). In general, a strong acids start with H and strong bases end with OH. Everything else you can assume is weak

Mai V 4L
Posts: 111
Joined: Fri Sep 28, 2018 12:23 am

Re: Strong/weak acids & bases

Postby Mai V 4L » Mon Mar 09, 2020 3:56 pm

Does somwone have a chart/graphic they used to help memorize this?

Julia Holsinger_1A
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Joined: Tue Feb 26, 2019 12:16 am

Re: Strong/weak acids & bases

Postby Julia Holsinger_1A » Tue Mar 10, 2020 5:54 pm

How do you figure out the conjugate acid or base for a given base or acid?

WGaines_2E
Posts: 47
Joined: Mon Nov 18, 2019 12:18 am

Re: Strong/weak acids & bases

Postby WGaines_2E » Tue Mar 10, 2020 9:32 pm

We are usually given weak acids and bases on exams and the dissociation values for those you don't need to remember, they should be given

Nicholas_Gladkov_2J
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Joined: Sat Aug 17, 2019 12:17 am

Re: Strong/weak acids & bases

Postby Nicholas_Gladkov_2J » Tue Mar 10, 2020 9:42 pm

Fdonovan 3D wrote:Are we going to have to know whether an acid or base is strong or weak just by its name or chemical formula? If so, how do we do know?


For the final, you should memorize the strong acids and strong bases are there are not that many.
Regarding weak acids and bases, given a scenario, and Ka and/or Kb, you should be able to know its pH, percent ionization, dissociation, etc.

Jessa Maheras 4F
Posts: 121
Joined: Fri Aug 02, 2019 12:16 am

Re: Strong/weak acids & bases

Postby Jessa Maheras 4F » Wed Mar 11, 2020 7:14 pm

CameronDis2K wrote:Yes, there's usually a pattern you can follow: anything with an OH- is usually a strong base (ex. KOH), and any compound preceded with an H and from the halogen group is usually a strong acid (HBr, HCl, etc.). But any compound with an NH3 is usually a weak acid, and others you can just memorize, like the weak acetic acid: CH3COOH.


These patterns are helpful!! I also find it helpful just to memorize.

Bryan Chen 1H
Posts: 58
Joined: Mon Jun 17, 2019 7:24 am

Re: Strong/weak acids & bases

Postby Bryan Chen 1H » Wed Mar 11, 2020 10:45 pm

yea memorize them


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