How can you tell

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Adam Kramer 1A
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Joined: Sat Aug 24, 2019 12:15 am

How can you tell

Postby Adam Kramer 1A » Sun Dec 01, 2019 10:38 am

How can you tell that the polyprotic acid or base is polyprotic by looking at the formula?

William Chan 1D
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Re: How can you tell

Postby William Chan 1D » Sun Dec 01, 2019 10:51 am

If there's more than one H in front of the anion, let's say,

H2SO4, or H3PO4

It'll be polyprotic because there is more than 1 hydrogen in front.

Juliet Stephenson 4E
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Joined: Wed Sep 18, 2019 12:21 am

Re: How can you tell

Postby Juliet Stephenson 4E » Sun Dec 01, 2019 11:05 am

Each H present in the anion will go on to form one hydronium ion. In HCl, one H begets one hydronium ion per molecule HCl (monoprotic). In H2S04, two H's will beget two hydronium ions per molecule H2So4 (biprotic/polyprotic). This is important to remember in calculating the pH of a substance.

Shutong Hou_1F
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Re: How can you tell

Postby Shutong Hou_1F » Sun Dec 01, 2019 3:06 pm

William Chan 1F wrote:If there's more than one H in front of the anion, let's say,

H2SO4, or H3PO4

It'll be polyprotic because there is more than 1 hydrogen in front.


Exactly! We should count the number of H atoms in the front of the anion, rather than count all H atoms, because not all H atoms would play a role in donating H atoms when dissociating in water. For example, CH3COOH is monoprotic, because only the last H atom would be donated, contributing to the fact that CH3COOH is an acid.

Shail Avasthi 2C
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Re: How can you tell

Postby Shail Avasthi 2C » Tue Dec 03, 2019 7:50 pm

If an acid has more than one hydrogen which it can dissociate, it is polyprotic.

Leila_4G
Posts: 114
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Re: How can you tell

Postby Leila_4G » Tue Dec 03, 2019 8:56 pm

Therefore, can only acids be polyprotic?
Because if a base is polyprotic doesn't that mean we are referring to its acidic properties of being able to give off protons so its an acid?

Alexa Hernandez 3k
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Re: How can you tell

Postby Alexa Hernandez 3k » Tue Dec 03, 2019 9:22 pm

A strong acid with several hidrogens

sarahsalama2E
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Re: How can you tell

Postby sarahsalama2E » Tue Dec 03, 2019 10:55 pm

Are polyprotic acids stronger or weaker with the more hydrogens that they have? I thought that if something has multiple hydrogens it is more likely to give off a proton, therefore dissociates more, and is therefore stronger of an acid.

005321227
Posts: 90
Joined: Sat Sep 07, 2019 12:15 am

Re: How can you tell

Postby 005321227 » Tue Dec 03, 2019 11:07 pm

make sure that the anion has more than one hydrogen!

AmyL_3L
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Joined: Fri Aug 09, 2019 12:17 am

Re: How can you tell

Postby AmyL_3L » Sat Dec 07, 2019 8:49 pm

Since polyprotic acids and bases donate or accept more than one proton, respectively, there must be more than one hydrogen in the anion.

105289321
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Joined: Sat Sep 07, 2019 12:15 am

Re: How can you tell

Postby 105289321 » Sat Dec 07, 2019 9:46 pm

If an atom can donate more than one H+

rohun2H
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Joined: Wed Sep 18, 2019 12:19 am

Re: How can you tell

Postby rohun2H » Sat Dec 07, 2019 10:13 pm

Typically, there will be more than one hydrogen.

Kandyce Lance 3E
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Re: How can you tell

Postby Kandyce Lance 3E » Sun Dec 06, 2020 5:17 pm

105289321 wrote:If an atom can donate more than one H+


Do you have an example of this?

Sukhkiran Kaur 3I
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Joined: Wed Sep 30, 2020 10:03 pm

Re: How can you tell

Postby Sukhkiran Kaur 3I » Sun Dec 06, 2020 6:04 pm

If there is more than one H in front, it'll be polyprotic.

Joshua Eidam 2A
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Joined: Wed Sep 30, 2020 9:58 pm

Re: How can you tell

Postby Joshua Eidam 2A » Thu Dec 10, 2020 11:57 pm

Sukhkiran_Kaur_3F wrote:If there is more than one H in front, it'll be polyprotic.

Is it specifically just in front or is it in general? I am a little confused as to whether or not all the H contribute to it being polyprotic?

Siwa Hwang 3G
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Joined: Wed Sep 30, 2020 9:48 pm

Re: How can you tell

Postby Siwa Hwang 3G » Fri Dec 11, 2020 1:44 am

Polyprotic atoms are capable of donating more than one protons.

Laura 3l
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Re: How can you tell

Postby Laura 3l » Fri Dec 11, 2020 1:46 am

Shail Avasthi 2C wrote:If an acid has more than one hydrogen which it can dissociate, it is polyprotic.

This makes sense, thank you!

Gicelle Rubin 1E
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Joined: Fri Oct 02, 2020 12:16 am

Re: How can you tell

Postby Gicelle Rubin 1E » Fri Dec 11, 2020 3:20 am

The anion has to have more than one h atom :)

DPatel_2L
Posts: 70
Joined: Wed Sep 30, 2020 9:41 pm

Re: How can you tell

Postby DPatel_2L » Fri Dec 11, 2020 8:03 pm

the anion has to have more than one H


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