Lewis acids and bases


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Mari Williams 1K
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Lewis acids and bases

Postby Mari Williams 1K » Sun Nov 15, 2020 8:55 pm

What's a good way to determine whether a compound is an acid or a base? It has to do with charge, right?

Neel Sharma 3F
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Re: Lewis acids and bases

Postby Neel Sharma 3F » Sun Nov 15, 2020 8:57 pm

Charge might be misleading sometimes and not show the whole picture. Instead look at whether the compound is electron deficient or rich. If it requires electrons to fulfill an octet then it is an Lewis acid or electron acceptor. If it can provide an electron then it is an Lewis base. Hope this helps!

Jason Knight - 1F
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Re: Lewis acids and bases

Postby Jason Knight - 1F » Sun Nov 15, 2020 8:59 pm

A Lewis acid is an atom that accepts an electron pair (Acid=Accepts). A Lewis base typically donates an electron pair and will have lone-pair electrons.

Irene Nguyen 2J
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Re: Lewis acids and bases

Postby Irene Nguyen 2J » Sun Nov 15, 2020 9:02 pm

Lewis acids and bases relate to accepting and gaining electrons to form covalent bonds. The Lewis base, such as an OH- ion will donate an electron to the Lewis acid, such as an H+, which accepts the electron. Hope this helps!

Lauren Mungo 1K
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Re: Lewis acids and bases

Postby Lauren Mungo 1K » Sun Nov 15, 2020 9:02 pm

Hi! Lewis acids accept an electron pair and lewis bases donate an electron pair. So molecules that have a positive charge are more likely to be lewis acids and molecules with a negative charge are more likely to be lewis bases.

Ruth Rosales 3D
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Re: Lewis acids and bases

Postby Ruth Rosales 3D » Sun Nov 15, 2020 9:05 pm

Hello! The way I am memorizing it is: Acid Accepts and Bases donates (electrons)

It basically just works for the acids but I remember that Acid and Accepts starts with the same letter.

Alejandro Gonzalez 2G
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Re: Lewis acids and bases

Postby Alejandro Gonzalez 2G » Sun Nov 15, 2020 9:35 pm

I find it helpful to think of Lewis acids as the electron deficient compound that accepts electrons whereas the Lewis base in a reaction is the compound or molecule that provides electrons (donates) to form a coordinate covalent bond.

Binyu You
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Re: Lewis acids and bases

Postby Binyu You » Fri Nov 20, 2020 8:17 am

Lewis acid accepts electrons. I just think a way to remember to better is that acid starts with a and accepts electron. Lewis base, on the other hand, donate electrons.

JaesalSoma1E
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Re: Lewis acids and bases

Postby JaesalSoma1E » Fri Nov 20, 2020 8:57 am

Lewis acids accept electron and lewis bases donate electrons. I remember by saying Acid=Accept.

Katie Le 3K
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Re: Lewis acids and bases

Postby Katie Le 3K » Fri Nov 20, 2020 8:23 pm

A helpful way is it draw out the lewis structures of the molecules and see which one has lone pair electrons. The one with lone pair electrons is the Lewis base.

Julianna Shimabukuro 1D
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Re: Lewis acids and bases

Postby Julianna Shimabukuro 1D » Fri Nov 20, 2020 9:14 pm

I remember the Lewis acids with the "a" in acids and "a" in accept as well. However, if that doesn't help you, you can always determine which is a Lewis acid and base by drawing the Lewis structures to see which has a lone pair of electrons. The one that has a lone pair of electrons will be the base since it can donate these electrons. The acid is the one that can accept more electrons to complete its octet or the number of electrons it needs to satisfy the amount of valence electrons in the structure.

Adrienne Yuh 2B
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Re: Lewis acids and bases

Postby Adrienne Yuh 2B » Fri Nov 20, 2020 9:17 pm

Lewis acids ACCEPT electrons, meaning they usually have a positive charge or full shells while bases donate since they have lone pair electrons and a negative charge.

AndrewNguyen_2H
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Re: Lewis acids and bases

Postby AndrewNguyen_2H » Fri Nov 20, 2020 9:26 pm

Lewis acid accepts an electron pair while the base is the donor. Look for coordinate covalent bonds because one element/molecule is always donating an electron to form the bond.

Joshua Chung 2D
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Re: Lewis acids and bases

Postby Joshua Chung 2D » Sun Nov 22, 2020 8:57 pm

Generally, you can determine which molecules accept (acids) or donate (bases) by looking at their respective Lewis Structures. Lone pair electrons usually indicate that the molecule is a base.

Daniela Santana 2L
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Re: Lewis acids and bases

Postby Daniela Santana 2L » Sun Nov 22, 2020 9:39 pm

Hi! A Lewis acid accepts electrons. A way to help you remember definition wise is Acid=Accepts. A Lewis base donates electrons.

Taha 2D
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Re: Lewis acids and bases

Postby Taha 2D » Sun Nov 22, 2020 9:44 pm

best way to see the difference is that a lewis acid accepts electrons while a lewis base donates them

Yolanda_Xing_3A
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Re: Lewis acids and bases

Postby Yolanda_Xing_3A » Sun Nov 29, 2020 9:39 am

Hi! Lewis acid always accepts an electron pair while Lewis base typically donates an electron pair and will have lone-pair electrons. This is also shown on the periodic table that the left column elements always donates e while close to the right column accept e.

Sreeram Kurada 3H
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Re: Lewis acids and bases

Postby Sreeram Kurada 3H » Sun Nov 29, 2020 9:51 am

Lewis acids accept electrons, while lewis bases donate electrons. Typically, you see cations to be lewis acids, while big molecules such as NH3 to be lewis bases.

Carly_Lipschitz_3H
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Re: Lewis acids and bases

Postby Carly_Lipschitz_3H » Tue Dec 01, 2020 11:32 am

A good way to determine whether a compound is an acid or a base is by remembering that lewis acids accept electrons. Lewis bases donate electrons. Charge isn't as important in determining whether a compound is an acid or a base. It is more useful to determine whether each compound is electron deficient or not instead.

Mary Gallo 1G
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Re: Lewis acids and bases

Postby Mary Gallo 1G » Tue Dec 01, 2020 1:26 pm

Lewis acids accept electrons while lewis bases donate electrons. The acids will usually have a positive charge and want electrons to neutralize the charge. Lewis bases will usually be negatively charged and willing to donate the extra electrons.

Jaclyn Schwartz 1I
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Re: Lewis acids and bases

Postby Jaclyn Schwartz 1I » Sun Dec 06, 2020 6:21 pm

I usually look at the formula. Acids are electron acceptors. So if you are to look at charges, H+ is what it will break into water. If it starts with H, it's most likely an acid because it will be the electron pair receptor. Bases are electron donors and in water will usually break into OH-. Bases might have an OH in them as an electron pair donor. So if you can see the charges in them, thats good but sometimes it's easier to simplify it. Another way is to look at the structures and identify which molecule would be donating an electron or H+ and which would accept that. Hopefully that will help you figure out which is which!

Kandyce Lance 3E
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Re: Lewis acids and bases

Postby Kandyce Lance 3E » Sat Dec 12, 2020 9:44 am

So Lewis and Bronsted acids/bases are only opposites or different from each other in the context we are defining a molecule?

Kandyce Lance 3E
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Re: Lewis acids and bases

Postby Kandyce Lance 3E » Sat Dec 12, 2020 9:46 am

Kandyce Lance 2L wrote:So Lewis and Bronsted acids/bases are only opposites or different from each other in the context we are defining a molecule?


In terms of the bronsted definition being focused on protons instead of electrons?


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