H30+ or OH-

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Chloe C 2H
Posts: 38
Joined: Mon Jan 09, 2023 9:19 am

H30+ or OH-

Postby Chloe C 2H » Sun Jan 22, 2023 8:31 pm

Does anyone have any tips for knowing if compounds will disassociate to H30+ or OH-?

Victoria Bouffard 1D
Posts: 35
Joined: Mon Jan 09, 2023 2:35 am

Re: H30+ or OH-

Postby Victoria Bouffard 1D » Sun Jan 22, 2023 8:41 pm

This will depend on if the compound is an acid or a base. Since acids are proton donors, they will dissociate to form H3O+ because the water molecule will pick up the released proton. The reverse is true for bases because they are proton acceptors. So, when they dissociate, they will form OH- because the water molecule loses a proton.

Emily Ang 2B
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Joined: Mon Jan 09, 2023 8:52 am

Re: H30+ or OH-

Postby Emily Ang 2B » Fri Jan 27, 2023 4:43 pm

Another thing to note about if it uses H3O+ or OH-, is that for strong acids and bases you will just have to calculate the concentration of H3O+ from the given acid and the conc. of OH- from the given base, without the ICE table. Then use the knowledge that pH + pOH = 14 to then find [H30+] or [OH-].

Skylar Smith 1E
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Joined: Wed Feb 17, 2021 12:16 am

Re: H30+ or OH-

Postby Skylar Smith 1E » Fri Jan 27, 2023 5:14 pm

A way to remember is to look if in the equation a proton is being donated or received. If donated then we will be using H30+. If being accepted then we use OH-

306025535
Posts: 39
Joined: Mon Jan 09, 2023 8:45 am

Re: H30+ or OH-

Postby 306025535 » Fri Jan 27, 2023 5:29 pm

Whether H30+ or OH- will form as a result of dissociation depends on whether an acid or base is being dissociated. If an acid is being dissociated, it will form H30+ as it is an acid donor (it has a hydrogen to give to H20. On the other hand, if its a base being dissociated, it will form OH- because the base acts as a proton acceptor and will adopt the hydrogen from he H20 making it OH-.

AbenaaMensahBonsu2F
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Joined: Mon Jan 09, 2023 9:09 am

Re: H30+ or OH-

Postby AbenaaMensahBonsu2F » Sat Jan 28, 2023 3:19 pm

Typically acids will donate their proton and generate H3O+. Bases, on the other hand, are proton acceptors and will generate OH-. I really don't think there is a super clear indicator by simply looking at the elements to see what they will do. I think noticing the patterns of the strong acid and strong base molecules to can aid in figuring out whether it will generate hydronium or hydroxide.

John_Sunthorn_3B
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Joined: Mon Jan 09, 2023 9:44 am

Re: H30+ or OH-

Postby John_Sunthorn_3B » Sat Jan 28, 2023 6:44 pm

Acids donate an H+ to water (thus leading to H3O+ when dissociated), while bases accept the proton (and thus leads to OH- when dissociated). It would be helpful to remember what constitutes as an acid and a base in order to identify how a compound will dissociate.

Acids react as follows: HA(aq) + H2O(l) --> A−(aq) + H3O+(aq)
Bases react as follows: B(aq) + H2O(l) --> BH+(aq) + OH−(aq)

(keep in mind the arrows will depend on the strength of the acid/base, but for simplicity I put a one way arrow)

John_Sunthorn_3B
Posts: 37
Joined: Mon Jan 09, 2023 9:44 am

Re: H30+ or OH-

Postby John_Sunthorn_3B » Sat Jan 28, 2023 6:44 pm

Acids donate an H+ to water (thus leading to H3O+ when dissociated), while bases accept the proton (and thus leads to OH- when dissociated). It would be helpful to remember what constitutes as an acid and a base in order to identify how a compound will dissociate.

Acids react as follows: HA(aq) + H2O(l) --> A−(aq) + H3O+(aq)
Bases react as follows: B(aq) + H2O(l) --> BH+(aq) + OH−(aq)

(keep in mind the arrows will depend on the strength of the acid/base, but for simplicity I put a one way arrow)

CharlotteHilsabe 1B
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Joined: Mon Jan 09, 2023 2:24 am

Re: H30+ or OH-

Postby CharlotteHilsabe 1B » Sun Jan 29, 2023 10:36 am

Acids are proton donors and therefore will donate a proton (H+) to the water surrounding them, creating H3O+.

Bases are proton acceptor and therefore will take a proton (H+) from the water surrounding them, creating OH-.

It is important to note though, that neutral water will always have both H3O+ and OH- molecules as water molecules bump into each other and either donate ahydrogen ion or accept one. This is called the Self - Ionization Reaction of water and is why the pH of neutral water is 7.

Dhruvi Mehta 1L
Posts: 34
Joined: Mon Jan 09, 2023 8:40 am

Re: H30+ or OH-

Postby Dhruvi Mehta 1L » Sun Jan 29, 2023 11:09 am

If you are working with an acid, then it will donate a proton to the water, and create H3o+ (the conjugate acid, as h3o+ is acidic). on the other hand, if you are working with a base, then it will take the proton from the water and create oh- (the conjugate base, as oh- is acidic).

mieke van daelen 2I
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Joined: Mon Jan 09, 2023 9:24 am

Re: H30+ or OH-

Postby mieke van daelen 2I » Sun Jan 29, 2023 12:23 pm

To determine this we must know whether the original compound is an acid or a base. Acids give protons and bases take protons. So if it is an acids it will give off a proton that the water takes up to form H3O+ (conjugate acid), and if it is a base, it will take a proton from the water leaving OH- (conjugate base)

405779380
Posts: 34
Joined: Mon Jan 09, 2023 9:45 am

Re: H30+ or OH-

Postby 405779380 » Sun Jan 29, 2023 12:27 pm

An acid will disassociate and donate a proton, creating H3O+. A base on the other hand will accept a proton and generate OH-.

Allyson_Khachaturov_3B
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Joined: Mon Jan 09, 2023 9:43 am

Re: H30+ or OH-

Postby Allyson_Khachaturov_3B » Sun Jan 29, 2023 12:50 pm

The first thing I normally do is figure out whether or not I am looking at an acid or a base. If I am looking at an acid, then I know that the acid will disassociate into H+ and bind to H20 to create H3O+. If I am looking at a base, I know that it will take an H+, thus resulting in an -OH from H2O. I hope this helps!

sherwin arian 1K
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Joined: Mon Jan 09, 2023 8:37 am

Re: H30+ or OH-

Postby sherwin arian 1K » Sun Jan 29, 2023 7:45 pm

If it is an acid in the reactants then it will donate an H+ so the product will have H3O+. If it is a base in the reactants it will accept an H+ so the product will have OH-.


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