Distinguishing between Strong and Weak Acids/Bases

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Aayush Patel 3B
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Joined: Thu Jul 25, 2019 12:17 am

Distinguishing between Strong and Weak Acids/Bases

Postby Aayush Patel 3B » Sun Dec 01, 2019 2:21 pm

How can someone distinguish a strong acid or base from a weak acid or base? How do you know if a compound will fully deprotonate or protonate in a solution?

Trinity Vu 1D
Posts: 53
Joined: Fri Aug 30, 2019 12:15 am

Re: Distinguishing between Strong and Weak Acids/Bases

Postby Trinity Vu 1D » Sun Dec 01, 2019 2:26 pm

An acid/base is considered strong or weak depending on whether or not it completely ionizes in a solution/water. One way to know is there was a 100% dissociation for an acid for example is by looking at the Ka value. Whenever the Ka is given you can generally assume its a weak acid because this means that there is still some [AH] in equilibrium therefore meaning AH didn't completely ionize. Since strong acids theoretically 100% dissociate, [AH]=0 and therefore you wouldn't be able to calculate Ka.

805373590
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Joined: Wed Sep 11, 2019 12:17 am

Re: Distinguishing between Strong and Weak Acids/Bases

Postby 805373590 » Sun Dec 01, 2019 2:34 pm

I think we only need to memorize the strong acids and bases outlined in the table from the fundamentals section J.

Max Madrzyk Dis 4G
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Joined: Wed Sep 18, 2019 12:21 am

Re: Distinguishing between Strong and Weak Acids/Bases

Postby Max Madrzyk Dis 4G » Sun Dec 01, 2019 3:00 pm

I think they're are like 7 strong acids and 8 strong bases so if you memorize those then you should be fine.

Verity Lai 2K
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Joined: Sat Aug 24, 2019 12:18 am

Re: Distinguishing between Strong and Weak Acids/Bases

Postby Verity Lai 2K » Sun Dec 01, 2019 4:15 pm

You distinguish if its a strong or weak acid/base depending on how much is dissociates in solution but I don't think there's any way for use to know that unless its given to us. I would memorize the ones from the book and you should be set.

pauline young 1L
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Joined: Thu Jul 11, 2019 12:15 am

Re: Distinguishing between Strong and Weak Acids/Bases

Postby pauline young 1L » Sun Dec 01, 2019 4:41 pm

i think you should memorize some of the common strong and weak acid/bases. other than that, there are some trends you can pick up on. for example, Dr. Lavelle mentioned that if there's a N involved, its probably a weak base.

Princess Jereza 3C
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Joined: Sat Jul 20, 2019 12:16 am

Re: Distinguishing between Strong and Weak Acids/Bases

Postby Princess Jereza 3C » Sun Dec 01, 2019 9:01 pm

In another way, we can see if there is a strong/weak acid or base present in the chemical reaction given, we can see if the reactant, let's say, an acid, is strong or weak based on the deprotonation of its H atoms in the chemical products shown, same thing with a reaction that has a base (protonation with OH-) that can result in hydroxide ions and water when an oxide or hydroxide ion is in solution.
Strong Acids: completely deprotonated in solution
Strong Bases: completely protonated in solution
Weak Acids: incompletely protonated in solution
Weak Bases: incompletely deprotonated in solution
I hope this helps

Princess Jereza 3C
Posts: 46
Joined: Sat Jul 20, 2019 12:16 am

Re: Distinguishing between Strong and Weak Acids/Bases

Postby Princess Jereza 3C » Sun Dec 01, 2019 9:03 pm

Princess Jereza 3C wrote:In another way, we can see if there is a strong/weak acid or base present in the chemical reaction given, we can see if the reactant, let's say, an acid, is strong or weak based on the deprotonation of its H atoms in the chemical products shown, same thing with a reaction that has a base (protonation with OH-) that can result in hydroxide ions and water when an oxide or hydroxide ion is in solution.
Strong Acids: completely deprotonated in solution
Strong Bases: completely protonated in solution
Weak Acids: incompletely protonated in solution
Weak Bases: incompletely deprotonated in solution
I hope this helps

I messed up on the second part


*Weak acids are incompletely deprotonated in solution while weak bases are incompletely protonated in solution* sorry!


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