Difference in PH between strong and weak acids

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405318478
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Difference in PH between strong and weak acids

Postby 405318478 » Mon Jan 20, 2020 4:16 pm

could someone explain why, at the same concentration, a weak acid would have a higher PH than a strong acid?

sarahsalama2E
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Re: Difference in PH between strong and weak acids

Postby sarahsalama2E » Mon Jan 20, 2020 4:22 pm

remember that pH and H concentration are inverses, so something with a very high hydronium (h+) ion concentration, would be very acidic meaning that that its very low on the pH scale (lower is more acidic and basic is higher). So because of this logic, we know that a weak acid who has a low hydronium ion concentration is not as acidic and is more basic than a strong acid, therefore it has a higher pH.

Joowon Seo 3A
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Re: Difference in PH between strong and weak acids

Postby Joowon Seo 3A » Mon Jan 20, 2020 6:19 pm

A weak acid does not give up it's protons as easily as a strong acid. Therefore, there is a less concentration of hydronium ions and therefore a lower pH

Hussain Chharawalla 1G
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Re: Difference in PH between strong and weak acids

Postby Hussain Chharawalla 1G » Mon Jan 20, 2020 6:41 pm

When adding a weak acid, how does the conjugate base affect pH?

ayushibanerjee06
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Re: Difference in PH between strong and weak acids

Postby ayushibanerjee06 » Mon Jan 20, 2020 8:35 pm

Remember that having a higher pH value means that it is not very acidic since it is closer to neutral pH = 7. Because of this, weaker acids have higher pHs because they are deprotonating less. Strong acids disassociate 100%, but since weak acids do not, their pH tends to be higher.

Katie Bart 1I
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Re: Difference in PH between strong and weak acids

Postby Katie Bart 1I » Tue Jan 21, 2020 10:43 am

The stronger the acid, the lower the pH. The weaker the acid, the closer to 7 it is.

Kaylee Clarke 1G
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Re: Difference in PH between strong and weak acids

Postby Kaylee Clarke 1G » Tue Jan 21, 2020 11:18 am

The strong acids have a lower pH because they fully dissociate and have a lower hydronium concentration. Weak acids are the opposite.

Luc Zelissen 1K
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Re: Difference in PH between strong and weak acids

Postby Luc Zelissen 1K » Tue Jan 21, 2020 9:08 pm

Kaylee Clarke 1G wrote:The strong acids have a lower pH because they fully dissociate and have a lower hydronium concentration. Weak acids are the opposite.

You are right that strong acids has a lower pH because they fully dissociate, but they have a higher hydronium concentration. The more H3O+ you have, the lower on the pH scale you go.

205291012
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Re: Difference in PH between strong and weak acids

Postby 205291012 » Tue Jan 21, 2020 11:31 pm

A strong acid has a smaller pH. A pH of 1 means it is stronger than a pH of 4. That's why a weak acid will have a higher pH than a strong acid.

Caroline Beecher 2H
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Re: Difference in PH between strong and weak acids

Postby Caroline Beecher 2H » Thu Jan 23, 2020 9:34 am

Additionally, it is good to note that smaller pKa or pKb values mean that the acid or base is stronger, while smaller Ka or Kb values mean that the acid or base is weaker.

Caroline Beecher 2H
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Re: Difference in PH between strong and weak acids

Postby Caroline Beecher 2H » Thu Jan 23, 2020 9:34 am

Additionally, it is good to note that smaller pKa or pKb values mean that the acid or base is stronger, while smaller Ka or Kb values mean that the acid or base is weaker.

LNgo 1G
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Re: Difference in PH between strong and weak acids

Postby LNgo 1G » Thu Jan 23, 2020 9:40 am

Strong acids dissociate more than weak acids, resulting in a higher hydronium concentration in the solution. Where pH=-log[H3O+] a higher concentration of hydronium correlates to a lower pH value.


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