strong and weak acids

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Cynthia Ulloa
Posts: 52
Joined: Fri Feb 23, 2018 3:02 am

strong and weak acids

Postby Cynthia Ulloa » Tue Feb 12, 2019 9:26 pm

Can someone explain why solutions of weak acids have a higher pH?

Becky Belisle 1A
Posts: 81
Joined: Fri Sep 28, 2018 12:18 am

Re: strong and weak acids

Postby Becky Belisle 1A » Tue Feb 12, 2019 9:58 pm

Solutions of strong acids have a higher pH than solutions of weak acids of the same the molarity. For weak acids: the weaker the acid, the greater the pKa.

Irene Zhou 1E
Posts: 73
Joined: Fri Sep 28, 2018 12:18 am

Re: strong and weak acids

Postby Irene Zhou 1E » Tue Feb 12, 2019 10:00 pm

Solutions of weak acids have a higher pH value than solutions of strong acids because it has a lower concentration of hydronium ions, so it is less acidic.

Alysa Rallistan 2G
Posts: 32
Joined: Thu Jan 17, 2019 12:16 am

Re: strong and weak acids

Postby Alysa Rallistan 2G » Thu Mar 07, 2019 12:16 am

Weak acids tend to have higher pH because they do not tend to fully dissociate into hydronium ions and their respective anions. When you calculate the pH of a solution, you take the -log of the concentration of Hydronium ions, for weak acids this concentration will be relatively low compared to strong bases, so when taking this calculation the smaller the number in the -log the higher the overall value (and thus pH) becomes

Shibhon_Shepard
Posts: 62
Joined: Wed Nov 15, 2017 3:04 am

Re: strong and weak acids

Postby Shibhon_Shepard » Fri Mar 15, 2019 1:26 pm

the more H3O+ ions there are the stronger the acid, so lower H3O+ ions means higher pH. (It's completely based on the H3O+ ions)

Catly Do 2E
Posts: 64
Joined: Fri Sep 28, 2018 12:24 am

Re: strong and weak acids

Postby Catly Do 2E » Fri Mar 15, 2019 3:01 pm

A weak acid has less % dissociation (less of the acid, or the [HA] is breaking down), so that means when you take the pH, the value will be higher.


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