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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Joined: Sat Sep 14, 2019 12:15 am

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 3C
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Re: How can you tell

Postby Shail Avasthi 3C » 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: 96
Joined: Sat Sep 14, 2019 12:17 am

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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Joined: Fri Aug 30, 2019 12:16 am

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
Posts: 50
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
Posts: 80
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.


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