Lewis Acids & Bases

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Michael Iter 2F
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Lewis Acids & Bases

Postby Michael Iter 2F » Sun Nov 08, 2020 5:30 pm

I'm still a bit confused as to how Lewis acids and bases relate to the traditional acids and bases I remember learning about in high school

Sydney Lam_2I
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Re: Lewis Acids & Bases

Postby Sydney Lam_2I » Sun Nov 08, 2020 5:32 pm

Hi,

How it relates is that giving an atom giving an electron away would make it a positive charge, acid, while an atom taking the electron would result in a negative charge, base. So, this is the start of the acid base section with the OH- and H+. This is really brief but I hope this helps!

Raashi Chaudhari 3B
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Re: Lewis Acids & Bases

Postby Raashi Chaudhari 3B » Mon Nov 09, 2020 9:10 am

The way I remember this is Lewis Acids Accept electron pairs (think Acid = Accepts), and Lewis Bases Donate electron pairs.
Lewis Acids include cations, electron-deficient central atoms, and polar double bonds. (ex: BF3, H+)
Lewis Bases include anions, molecules w lone pairs, atoms w excess electrons. (NH3, F-, -OH)

sophie esherick 3H
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Re: Lewis Acids & Bases

Postby sophie esherick 3H » Mon Nov 09, 2020 9:33 am

Lewis Acids are electron-pair acceptors, they are usually electron deficient so think of cations (H+, K+) or electron-deficient central atoms (BF3, AlCl3).
A Lewis base is a molecule or ion that can donate a pair of electrons to form a bond (electron donors). An atom, ion, or molecule with a lone-pair of electrons/excess electrons can be a Lewis base (e.g. OH-, F-, NH3, CN-).

Heidi Buri 2I
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Re: Lewis Acids & Bases

Postby Heidi Buri 2I » Mon Nov 30, 2020 1:20 pm

Hi! For Lewis acids and bases, lewis acids accept pairs of electrons and Lewis bases donate pairs of electrons. An example of a lewis acid is H+ as it can accept a pair of electrons. An example of a Lewis base is OH- as it can donate a pair of electrons. This relates to traditional acids and bases as acids are neon to produce H+ in an aqueous solution and bases are known to produce OH- in an aqueous solution.

Libby Dillon - 1A
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Re: Lewis Acids & Bases

Postby Libby Dillon - 1A » Wed Dec 02, 2020 1:53 pm

Lewis Acids and Bases can be identified as either electron donors or electron acceptors. So in a chemical reaction, the species accepting or gaining the electron pair is a Lewis Acid, like BF3 and H+. The species donating or losing the electron pair is a Lewis Base, like NH3 and OH-.

Jasraj Parmar 3H
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Re: Lewis Acids & Bases

Postby Jasraj Parmar 3H » Wed Dec 02, 2020 7:51 pm

Lewis acids are electron poor and can be positively charged. Lewis bases are electron rich and can be negatively charged.

Isabel_Eslabon_2G
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Re: Lewis Acids & Bases

Postby Isabel_Eslabon_2G » Wed Dec 02, 2020 9:55 pm

Lewis Acids are electron acceptors (I remember that because acids and acceptor both start with 'a'). These acids are electron deficient. I usually remember that if it has a positive charge, it can accept an electron (cations).

Lewis Bases are electron donors. These bases may have negative charges (anions).

I'm not sure what you mean by 'traditional acids and bases', maybe the Brønsted-Lowry (BL) acids and bases?
BL Acids are proton (H+) donors.
BL Bases are proton (H+) acceptors.

Yun Su Choi 3G
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Re: Lewis Acids & Bases

Postby Yun Su Choi 3G » Thu Dec 03, 2020 10:28 am

Does this mean that lewis acids and bases don't have to always ionize in water like how Bronsted acids and bases do?
To clarify with an example, BF3 can be considered as a lewis acid just by accepting an electron pair from F- without having to dissociate anything.

Eunice_Castro_1G
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Re: Lewis Acids & Bases

Postby Eunice_Castro_1G » Thu Dec 03, 2020 10:52 am

Hi! I am not sure what you learned in high school about acids and bases, but you can look at it in two ways:
1.Acids-accept pair of electrons
Bases-Donate pair of electrons

2. Acids-donate protons
Bases-accept protons

Hope this helps!

Nan_Guan_1L
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Re: Lewis Acids & Bases

Postby Nan_Guan_1L » Sun Dec 06, 2020 10:10 am

Just to add to the discussion above:
I usually think that Lewis acid and base as a bigger, more general group and it includes the traditional acid and base concept we’ve been taught in high school.
Some of the compounds might not be traditionally considered as an acid but it may be considered as a Lewis acid for example.

Kyle Dizon 3A
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Re: Lewis Acids & Bases

Postby Kyle Dizon 3A » Sun Dec 06, 2020 10:12 am

To add on I have always approached acids and bases by creating my theory that lewis acids are electron deprived and bases are electron rich that can donate to these acids.

abby hyman
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Re: Lewis Acids & Bases

Postby abby hyman » Sun Dec 06, 2020 11:37 am

I think the way that it is most similar to high school chemistry is in the fact that a lewis acid is electron-deficient and the lewis base is electron-rich and the electron-rich donates to the electron-deficient.


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