Which acid/base does a strong base/acid react when added to a buffer solution? The Next CEO of Stack OverflowHow to calculate the pH of a buffered solution with Henderson Hasselbalch?What's happening at the beginning of a weak acid titration?Buffer and strong acidWhy is only one part of buffer in the reactants side?What is causing the buffer region in a weak acid - strong base titration?Why is the hydrolysis of the conjugate base of a weak acid neglected in buffer solutions?Buffer Solution Problem (Acid/Conjugate Base)Why must a buffer solution contain both a weak acid and a salt solution of its conjugate base?How is preparing a buffer possible?Error with explaination of shape of weak acid strong base titration?

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Which acid/base does a strong base/acid react when added to a buffer solution?

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Which acid/base does a strong base/acid react when added to a buffer solution?



The Next CEO of Stack OverflowHow to calculate the pH of a buffered solution with Henderson Hasselbalch?What's happening at the beginning of a weak acid titration?Buffer and strong acidWhy is only one part of buffer in the reactants side?What is causing the buffer region in a weak acid - strong base titration?Why is the hydrolysis of the conjugate base of a weak acid neglected in buffer solutions?Buffer Solution Problem (Acid/Conjugate Base)Why must a buffer solution contain both a weak acid and a salt solution of its conjugate base?How is preparing a buffer possible?Error with explaination of shape of weak acid strong base titration?










1












$begingroup$


I'm in high school chemistry and just learning about buffer solutions. For example, given a buffered solution of $ceCH3COOH$ and $ceNaCH3COO$ with $K_a = 1.8 times 10^-5$, we might want to find what the pH will become if $ce0.010 M KOH$ is added. Given the dissociation of acetic acid:



$$ceCH3COOH + H2O <=> H3O+ + CH3COO-$$



My question is, which acid ($ceCH3COOH$ or the conjugate $ceH3O+$) will the base $ceKOH$ react with? My teacher said that the base will react with $ceH3O+$ to shift equilibrium in the forward direction, but why wouldn't it react with $ceCH3COOH$ since it also is an acid?



Is there a specific rule that an added acid/base will react only with the base/acid in the product side of the reaction?










share|improve this question









New contributor




Andrew Li is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.







$endgroup$











  • $begingroup$
    They're all in equilibrium together. It would be mistake to ask which one reacted. Whatever you pick is still part of the equilibrium that needs to readjust.
    $endgroup$
    – Zhe
    2 hours ago










  • $begingroup$
    "My teacher said that the base will react with $ceH3O+$ to shift equilibrium in the $colorredreverse$ direction,".I think to shift the equilibrium in the $colorgreenforward$ direction.
    $endgroup$
    – Adnan AL-Amleh
    1 hour ago















1












$begingroup$


I'm in high school chemistry and just learning about buffer solutions. For example, given a buffered solution of $ceCH3COOH$ and $ceNaCH3COO$ with $K_a = 1.8 times 10^-5$, we might want to find what the pH will become if $ce0.010 M KOH$ is added. Given the dissociation of acetic acid:



$$ceCH3COOH + H2O <=> H3O+ + CH3COO-$$



My question is, which acid ($ceCH3COOH$ or the conjugate $ceH3O+$) will the base $ceKOH$ react with? My teacher said that the base will react with $ceH3O+$ to shift equilibrium in the forward direction, but why wouldn't it react with $ceCH3COOH$ since it also is an acid?



Is there a specific rule that an added acid/base will react only with the base/acid in the product side of the reaction?










share|improve this question









New contributor




Andrew Li is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.







$endgroup$











  • $begingroup$
    They're all in equilibrium together. It would be mistake to ask which one reacted. Whatever you pick is still part of the equilibrium that needs to readjust.
    $endgroup$
    – Zhe
    2 hours ago










  • $begingroup$
    "My teacher said that the base will react with $ceH3O+$ to shift equilibrium in the $colorredreverse$ direction,".I think to shift the equilibrium in the $colorgreenforward$ direction.
    $endgroup$
    – Adnan AL-Amleh
    1 hour ago













1












1








1





$begingroup$


I'm in high school chemistry and just learning about buffer solutions. For example, given a buffered solution of $ceCH3COOH$ and $ceNaCH3COO$ with $K_a = 1.8 times 10^-5$, we might want to find what the pH will become if $ce0.010 M KOH$ is added. Given the dissociation of acetic acid:



$$ceCH3COOH + H2O <=> H3O+ + CH3COO-$$



My question is, which acid ($ceCH3COOH$ or the conjugate $ceH3O+$) will the base $ceKOH$ react with? My teacher said that the base will react with $ceH3O+$ to shift equilibrium in the forward direction, but why wouldn't it react with $ceCH3COOH$ since it also is an acid?



Is there a specific rule that an added acid/base will react only with the base/acid in the product side of the reaction?










share|improve this question









New contributor




Andrew Li is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.







$endgroup$




I'm in high school chemistry and just learning about buffer solutions. For example, given a buffered solution of $ceCH3COOH$ and $ceNaCH3COO$ with $K_a = 1.8 times 10^-5$, we might want to find what the pH will become if $ce0.010 M KOH$ is added. Given the dissociation of acetic acid:



$$ceCH3COOH + H2O <=> H3O+ + CH3COO-$$



My question is, which acid ($ceCH3COOH$ or the conjugate $ceH3O+$) will the base $ceKOH$ react with? My teacher said that the base will react with $ceH3O+$ to shift equilibrium in the forward direction, but why wouldn't it react with $ceCH3COOH$ since it also is an acid?



Is there a specific rule that an added acid/base will react only with the base/acid in the product side of the reaction?







acid-base equilibrium






share|improve this question









New contributor




Andrew Li is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.











share|improve this question









New contributor




Andrew Li is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.









share|improve this question




share|improve this question








edited 40 mins ago







Andrew Li













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Andrew Li is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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asked 2 hours ago









Andrew LiAndrew Li

1084




1084




New contributor




Andrew Li is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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New contributor





Andrew Li is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.






Andrew Li is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.











  • $begingroup$
    They're all in equilibrium together. It would be mistake to ask which one reacted. Whatever you pick is still part of the equilibrium that needs to readjust.
    $endgroup$
    – Zhe
    2 hours ago










  • $begingroup$
    "My teacher said that the base will react with $ceH3O+$ to shift equilibrium in the $colorredreverse$ direction,".I think to shift the equilibrium in the $colorgreenforward$ direction.
    $endgroup$
    – Adnan AL-Amleh
    1 hour ago
















  • $begingroup$
    They're all in equilibrium together. It would be mistake to ask which one reacted. Whatever you pick is still part of the equilibrium that needs to readjust.
    $endgroup$
    – Zhe
    2 hours ago










  • $begingroup$
    "My teacher said that the base will react with $ceH3O+$ to shift equilibrium in the $colorredreverse$ direction,".I think to shift the equilibrium in the $colorgreenforward$ direction.
    $endgroup$
    – Adnan AL-Amleh
    1 hour ago















$begingroup$
They're all in equilibrium together. It would be mistake to ask which one reacted. Whatever you pick is still part of the equilibrium that needs to readjust.
$endgroup$
– Zhe
2 hours ago




$begingroup$
They're all in equilibrium together. It would be mistake to ask which one reacted. Whatever you pick is still part of the equilibrium that needs to readjust.
$endgroup$
– Zhe
2 hours ago












$begingroup$
"My teacher said that the base will react with $ceH3O+$ to shift equilibrium in the $colorredreverse$ direction,".I think to shift the equilibrium in the $colorgreenforward$ direction.
$endgroup$
– Adnan AL-Amleh
1 hour ago




$begingroup$
"My teacher said that the base will react with $ceH3O+$ to shift equilibrium in the $colorredreverse$ direction,".I think to shift the equilibrium in the $colorgreenforward$ direction.
$endgroup$
– Adnan AL-Amleh
1 hour ago










3 Answers
3






active

oldest

votes


















3












$begingroup$

$$ceCH3COOH + H2O <=> H3O+ + CH3COO-$$




My question is, which acid (CH3COOH or the conjugate H3O+) will the base KOH react with?




You have to satisfy two equilibria, the one you wrote and the auto-dissociation of water.



$$ceH3O+ + OH- <=> 2 H2O$$



If you add up the two reaction, you get a third one:



$$ceCH3COOH + OH- <=> H2O + CH3COO-$$



You can go either way (use the second or the third reaction) to explain that $ceOH-$ is part of a neutralization reaction. As a consequence, the concentration of $ceCH3COO-$ increases and that of $ceCH3COOH$ and hydronium decreases.



Hydroxide reacts with hydronium



In this case, you would invoke the second reaction. There is more hydroxide (you are adding sufficient KOH to raise the concentration to 0.01 M) than hydronium (at about pH = 5, the buffer will contain about $pue-5$ M). As the hydronium gets neutralized, the weak acid equilibrium (first reaction) will shift forward (not reverse - typo in the question), making more hydronium, which will get neutralized etc.



Hydroxide reacts with acetic acid



In a different explanation that results in the same answer, you could say the hydroxide turns some of the weak acid into weak base (third reaction). As a result, the weak acid / weak base concentration ratio will change, causing a net reverse shift in the weak acid equilibrium (first reaction) and lowering the hydronium concentration.



Which way is better?



It is personal preference. If we knew how fast the two reactions go, we might choose the faster one, but we don't. For figuring out the equilibrium concentrations and the pH, it does not matter.




Is there a specific rule that an added acid/base will react only with the base/acid in the product side of the reaction?




No, and you can always combine two equilibrium reactions with overlapping species (like the hydronium ion in the first and second reaction) to arrive at a third that also has to be at equilibrium.






share|improve this answer











$endgroup$












  • $begingroup$
    "that the concentration of $~ce OH−$ $colorredtextdrops$ and the concentration of $~ce CH3COOH$ $colorredtextincreases$."I think:that the concentration of $ce OH−$ $colorgreentextincreases$ and the concentration of$ce CH3COOH$ $colorgreentextdecreases$.
    $endgroup$
    – Adnan AL-Amleh
    1 hour ago










  • $begingroup$
    Thanks for the comprehensive answer. One question: you said that the direction I choose shouldn't affect pH. But in the Henderson-Hasselbalch equation don't you have to compute $-log([base]/[acid])$? If I choose different directions, won't the new concentrations of base and acid be different?
    $endgroup$
    – Andrew Li
    33 mins ago










  • $begingroup$
    @Adnan AL-Amleh I fixed my typo: The neutralization reaction results in a drop of hydroxide and weak acid, while the concentration of weak base increases.
    $endgroup$
    – Karsten Theis
    22 mins ago










  • $begingroup$
    @Andrew_Li I had a typo which I fixed, and I revised my answer to address your follow-up question. No matter which reaction you start with, the ratio of weak base to weak acid concentration will increase, so the pH will increase. You expect that because that is what strong bases do. Because the solution is buffered, the change is much smaller than it would be for pure water, but it still changes a bit in that direction.
    $endgroup$
    – Karsten Theis
    16 mins ago


















1












$begingroup$

The hydroxide ion reacts with the hydronium ion (I hate that name; I prefer the simpler "hydrogen ion") to increase the concentration of water and decrease the concentration of hydrogen ion. To restore the equilibrium, now more acetic acid will ionize, shifting the equilibrium to the right as you have it written above.






share|improve this answer








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Charlie Amelotti is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.






$endgroup$




















    0












    $begingroup$

    Zhe's comment is not wrong, but I'd say that your teacher isn't either.



    Consider a 0.1 molar solution of acetic acid. The water will be about 55 molar.



    The twist here is that the proton of the hydronium ion is very liable in water. In other words, the proton exchange between water molecules happens very very fast. That is why using a mineral acid makes a solution very conductive. So just based on chance, a hydroxide ion is more likely to reaction with a hydronium ion than an acetic acid molecule. Hence your teacher's remark.



    However Zhe is correct in that it really doesn't make a difference overall. The H+/acetate/acetic acid equilibrium will be established "fairly" quickly.






    share|improve this answer









    $endgroup$













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      3 Answers
      3






      active

      oldest

      votes








      3 Answers
      3






      active

      oldest

      votes









      active

      oldest

      votes






      active

      oldest

      votes









      3












      $begingroup$

      $$ceCH3COOH + H2O <=> H3O+ + CH3COO-$$




      My question is, which acid (CH3COOH or the conjugate H3O+) will the base KOH react with?




      You have to satisfy two equilibria, the one you wrote and the auto-dissociation of water.



      $$ceH3O+ + OH- <=> 2 H2O$$



      If you add up the two reaction, you get a third one:



      $$ceCH3COOH + OH- <=> H2O + CH3COO-$$



      You can go either way (use the second or the third reaction) to explain that $ceOH-$ is part of a neutralization reaction. As a consequence, the concentration of $ceCH3COO-$ increases and that of $ceCH3COOH$ and hydronium decreases.



      Hydroxide reacts with hydronium



      In this case, you would invoke the second reaction. There is more hydroxide (you are adding sufficient KOH to raise the concentration to 0.01 M) than hydronium (at about pH = 5, the buffer will contain about $pue-5$ M). As the hydronium gets neutralized, the weak acid equilibrium (first reaction) will shift forward (not reverse - typo in the question), making more hydronium, which will get neutralized etc.



      Hydroxide reacts with acetic acid



      In a different explanation that results in the same answer, you could say the hydroxide turns some of the weak acid into weak base (third reaction). As a result, the weak acid / weak base concentration ratio will change, causing a net reverse shift in the weak acid equilibrium (first reaction) and lowering the hydronium concentration.



      Which way is better?



      It is personal preference. If we knew how fast the two reactions go, we might choose the faster one, but we don't. For figuring out the equilibrium concentrations and the pH, it does not matter.




      Is there a specific rule that an added acid/base will react only with the base/acid in the product side of the reaction?




      No, and you can always combine two equilibrium reactions with overlapping species (like the hydronium ion in the first and second reaction) to arrive at a third that also has to be at equilibrium.






      share|improve this answer











      $endgroup$












      • $begingroup$
        "that the concentration of $~ce OH−$ $colorredtextdrops$ and the concentration of $~ce CH3COOH$ $colorredtextincreases$."I think:that the concentration of $ce OH−$ $colorgreentextincreases$ and the concentration of$ce CH3COOH$ $colorgreentextdecreases$.
        $endgroup$
        – Adnan AL-Amleh
        1 hour ago










      • $begingroup$
        Thanks for the comprehensive answer. One question: you said that the direction I choose shouldn't affect pH. But in the Henderson-Hasselbalch equation don't you have to compute $-log([base]/[acid])$? If I choose different directions, won't the new concentrations of base and acid be different?
        $endgroup$
        – Andrew Li
        33 mins ago










      • $begingroup$
        @Adnan AL-Amleh I fixed my typo: The neutralization reaction results in a drop of hydroxide and weak acid, while the concentration of weak base increases.
        $endgroup$
        – Karsten Theis
        22 mins ago










      • $begingroup$
        @Andrew_Li I had a typo which I fixed, and I revised my answer to address your follow-up question. No matter which reaction you start with, the ratio of weak base to weak acid concentration will increase, so the pH will increase. You expect that because that is what strong bases do. Because the solution is buffered, the change is much smaller than it would be for pure water, but it still changes a bit in that direction.
        $endgroup$
        – Karsten Theis
        16 mins ago















      3












      $begingroup$

      $$ceCH3COOH + H2O <=> H3O+ + CH3COO-$$




      My question is, which acid (CH3COOH or the conjugate H3O+) will the base KOH react with?




      You have to satisfy two equilibria, the one you wrote and the auto-dissociation of water.



      $$ceH3O+ + OH- <=> 2 H2O$$



      If you add up the two reaction, you get a third one:



      $$ceCH3COOH + OH- <=> H2O + CH3COO-$$



      You can go either way (use the second or the third reaction) to explain that $ceOH-$ is part of a neutralization reaction. As a consequence, the concentration of $ceCH3COO-$ increases and that of $ceCH3COOH$ and hydronium decreases.



      Hydroxide reacts with hydronium



      In this case, you would invoke the second reaction. There is more hydroxide (you are adding sufficient KOH to raise the concentration to 0.01 M) than hydronium (at about pH = 5, the buffer will contain about $pue-5$ M). As the hydronium gets neutralized, the weak acid equilibrium (first reaction) will shift forward (not reverse - typo in the question), making more hydronium, which will get neutralized etc.



      Hydroxide reacts with acetic acid



      In a different explanation that results in the same answer, you could say the hydroxide turns some of the weak acid into weak base (third reaction). As a result, the weak acid / weak base concentration ratio will change, causing a net reverse shift in the weak acid equilibrium (first reaction) and lowering the hydronium concentration.



      Which way is better?



      It is personal preference. If we knew how fast the two reactions go, we might choose the faster one, but we don't. For figuring out the equilibrium concentrations and the pH, it does not matter.




      Is there a specific rule that an added acid/base will react only with the base/acid in the product side of the reaction?




      No, and you can always combine two equilibrium reactions with overlapping species (like the hydronium ion in the first and second reaction) to arrive at a third that also has to be at equilibrium.






      share|improve this answer











      $endgroup$












      • $begingroup$
        "that the concentration of $~ce OH−$ $colorredtextdrops$ and the concentration of $~ce CH3COOH$ $colorredtextincreases$."I think:that the concentration of $ce OH−$ $colorgreentextincreases$ and the concentration of$ce CH3COOH$ $colorgreentextdecreases$.
        $endgroup$
        – Adnan AL-Amleh
        1 hour ago










      • $begingroup$
        Thanks for the comprehensive answer. One question: you said that the direction I choose shouldn't affect pH. But in the Henderson-Hasselbalch equation don't you have to compute $-log([base]/[acid])$? If I choose different directions, won't the new concentrations of base and acid be different?
        $endgroup$
        – Andrew Li
        33 mins ago










      • $begingroup$
        @Adnan AL-Amleh I fixed my typo: The neutralization reaction results in a drop of hydroxide and weak acid, while the concentration of weak base increases.
        $endgroup$
        – Karsten Theis
        22 mins ago










      • $begingroup$
        @Andrew_Li I had a typo which I fixed, and I revised my answer to address your follow-up question. No matter which reaction you start with, the ratio of weak base to weak acid concentration will increase, so the pH will increase. You expect that because that is what strong bases do. Because the solution is buffered, the change is much smaller than it would be for pure water, but it still changes a bit in that direction.
        $endgroup$
        – Karsten Theis
        16 mins ago













      3












      3








      3





      $begingroup$

      $$ceCH3COOH + H2O <=> H3O+ + CH3COO-$$




      My question is, which acid (CH3COOH or the conjugate H3O+) will the base KOH react with?




      You have to satisfy two equilibria, the one you wrote and the auto-dissociation of water.



      $$ceH3O+ + OH- <=> 2 H2O$$



      If you add up the two reaction, you get a third one:



      $$ceCH3COOH + OH- <=> H2O + CH3COO-$$



      You can go either way (use the second or the third reaction) to explain that $ceOH-$ is part of a neutralization reaction. As a consequence, the concentration of $ceCH3COO-$ increases and that of $ceCH3COOH$ and hydronium decreases.



      Hydroxide reacts with hydronium



      In this case, you would invoke the second reaction. There is more hydroxide (you are adding sufficient KOH to raise the concentration to 0.01 M) than hydronium (at about pH = 5, the buffer will contain about $pue-5$ M). As the hydronium gets neutralized, the weak acid equilibrium (first reaction) will shift forward (not reverse - typo in the question), making more hydronium, which will get neutralized etc.



      Hydroxide reacts with acetic acid



      In a different explanation that results in the same answer, you could say the hydroxide turns some of the weak acid into weak base (third reaction). As a result, the weak acid / weak base concentration ratio will change, causing a net reverse shift in the weak acid equilibrium (first reaction) and lowering the hydronium concentration.



      Which way is better?



      It is personal preference. If we knew how fast the two reactions go, we might choose the faster one, but we don't. For figuring out the equilibrium concentrations and the pH, it does not matter.




      Is there a specific rule that an added acid/base will react only with the base/acid in the product side of the reaction?




      No, and you can always combine two equilibrium reactions with overlapping species (like the hydronium ion in the first and second reaction) to arrive at a third that also has to be at equilibrium.






      share|improve this answer











      $endgroup$



      $$ceCH3COOH + H2O <=> H3O+ + CH3COO-$$




      My question is, which acid (CH3COOH or the conjugate H3O+) will the base KOH react with?




      You have to satisfy two equilibria, the one you wrote and the auto-dissociation of water.



      $$ceH3O+ + OH- <=> 2 H2O$$



      If you add up the two reaction, you get a third one:



      $$ceCH3COOH + OH- <=> H2O + CH3COO-$$



      You can go either way (use the second or the third reaction) to explain that $ceOH-$ is part of a neutralization reaction. As a consequence, the concentration of $ceCH3COO-$ increases and that of $ceCH3COOH$ and hydronium decreases.



      Hydroxide reacts with hydronium



      In this case, you would invoke the second reaction. There is more hydroxide (you are adding sufficient KOH to raise the concentration to 0.01 M) than hydronium (at about pH = 5, the buffer will contain about $pue-5$ M). As the hydronium gets neutralized, the weak acid equilibrium (first reaction) will shift forward (not reverse - typo in the question), making more hydronium, which will get neutralized etc.



      Hydroxide reacts with acetic acid



      In a different explanation that results in the same answer, you could say the hydroxide turns some of the weak acid into weak base (third reaction). As a result, the weak acid / weak base concentration ratio will change, causing a net reverse shift in the weak acid equilibrium (first reaction) and lowering the hydronium concentration.



      Which way is better?



      It is personal preference. If we knew how fast the two reactions go, we might choose the faster one, but we don't. For figuring out the equilibrium concentrations and the pH, it does not matter.




      Is there a specific rule that an added acid/base will react only with the base/acid in the product side of the reaction?




      No, and you can always combine two equilibrium reactions with overlapping species (like the hydronium ion in the first and second reaction) to arrive at a third that also has to be at equilibrium.







      share|improve this answer














      share|improve this answer



      share|improve this answer








      edited 19 mins ago

























      answered 2 hours ago









      Karsten TheisKarsten Theis

      3,697541




      3,697541











      • $begingroup$
        "that the concentration of $~ce OH−$ $colorredtextdrops$ and the concentration of $~ce CH3COOH$ $colorredtextincreases$."I think:that the concentration of $ce OH−$ $colorgreentextincreases$ and the concentration of$ce CH3COOH$ $colorgreentextdecreases$.
        $endgroup$
        – Adnan AL-Amleh
        1 hour ago










      • $begingroup$
        Thanks for the comprehensive answer. One question: you said that the direction I choose shouldn't affect pH. But in the Henderson-Hasselbalch equation don't you have to compute $-log([base]/[acid])$? If I choose different directions, won't the new concentrations of base and acid be different?
        $endgroup$
        – Andrew Li
        33 mins ago










      • $begingroup$
        @Adnan AL-Amleh I fixed my typo: The neutralization reaction results in a drop of hydroxide and weak acid, while the concentration of weak base increases.
        $endgroup$
        – Karsten Theis
        22 mins ago










      • $begingroup$
        @Andrew_Li I had a typo which I fixed, and I revised my answer to address your follow-up question. No matter which reaction you start with, the ratio of weak base to weak acid concentration will increase, so the pH will increase. You expect that because that is what strong bases do. Because the solution is buffered, the change is much smaller than it would be for pure water, but it still changes a bit in that direction.
        $endgroup$
        – Karsten Theis
        16 mins ago
















      • $begingroup$
        "that the concentration of $~ce OH−$ $colorredtextdrops$ and the concentration of $~ce CH3COOH$ $colorredtextincreases$."I think:that the concentration of $ce OH−$ $colorgreentextincreases$ and the concentration of$ce CH3COOH$ $colorgreentextdecreases$.
        $endgroup$
        – Adnan AL-Amleh
        1 hour ago










      • $begingroup$
        Thanks for the comprehensive answer. One question: you said that the direction I choose shouldn't affect pH. But in the Henderson-Hasselbalch equation don't you have to compute $-log([base]/[acid])$? If I choose different directions, won't the new concentrations of base and acid be different?
        $endgroup$
        – Andrew Li
        33 mins ago










      • $begingroup$
        @Adnan AL-Amleh I fixed my typo: The neutralization reaction results in a drop of hydroxide and weak acid, while the concentration of weak base increases.
        $endgroup$
        – Karsten Theis
        22 mins ago










      • $begingroup$
        @Andrew_Li I had a typo which I fixed, and I revised my answer to address your follow-up question. No matter which reaction you start with, the ratio of weak base to weak acid concentration will increase, so the pH will increase. You expect that because that is what strong bases do. Because the solution is buffered, the change is much smaller than it would be for pure water, but it still changes a bit in that direction.
        $endgroup$
        – Karsten Theis
        16 mins ago















      $begingroup$
      "that the concentration of $~ce OH−$ $colorredtextdrops$ and the concentration of $~ce CH3COOH$ $colorredtextincreases$."I think:that the concentration of $ce OH−$ $colorgreentextincreases$ and the concentration of$ce CH3COOH$ $colorgreentextdecreases$.
      $endgroup$
      – Adnan AL-Amleh
      1 hour ago




      $begingroup$
      "that the concentration of $~ce OH−$ $colorredtextdrops$ and the concentration of $~ce CH3COOH$ $colorredtextincreases$."I think:that the concentration of $ce OH−$ $colorgreentextincreases$ and the concentration of$ce CH3COOH$ $colorgreentextdecreases$.
      $endgroup$
      – Adnan AL-Amleh
      1 hour ago












      $begingroup$
      Thanks for the comprehensive answer. One question: you said that the direction I choose shouldn't affect pH. But in the Henderson-Hasselbalch equation don't you have to compute $-log([base]/[acid])$? If I choose different directions, won't the new concentrations of base and acid be different?
      $endgroup$
      – Andrew Li
      33 mins ago




      $begingroup$
      Thanks for the comprehensive answer. One question: you said that the direction I choose shouldn't affect pH. But in the Henderson-Hasselbalch equation don't you have to compute $-log([base]/[acid])$? If I choose different directions, won't the new concentrations of base and acid be different?
      $endgroup$
      – Andrew Li
      33 mins ago












      $begingroup$
      @Adnan AL-Amleh I fixed my typo: The neutralization reaction results in a drop of hydroxide and weak acid, while the concentration of weak base increases.
      $endgroup$
      – Karsten Theis
      22 mins ago




      $begingroup$
      @Adnan AL-Amleh I fixed my typo: The neutralization reaction results in a drop of hydroxide and weak acid, while the concentration of weak base increases.
      $endgroup$
      – Karsten Theis
      22 mins ago












      $begingroup$
      @Andrew_Li I had a typo which I fixed, and I revised my answer to address your follow-up question. No matter which reaction you start with, the ratio of weak base to weak acid concentration will increase, so the pH will increase. You expect that because that is what strong bases do. Because the solution is buffered, the change is much smaller than it would be for pure water, but it still changes a bit in that direction.
      $endgroup$
      – Karsten Theis
      16 mins ago




      $begingroup$
      @Andrew_Li I had a typo which I fixed, and I revised my answer to address your follow-up question. No matter which reaction you start with, the ratio of weak base to weak acid concentration will increase, so the pH will increase. You expect that because that is what strong bases do. Because the solution is buffered, the change is much smaller than it would be for pure water, but it still changes a bit in that direction.
      $endgroup$
      – Karsten Theis
      16 mins ago











      1












      $begingroup$

      The hydroxide ion reacts with the hydronium ion (I hate that name; I prefer the simpler "hydrogen ion") to increase the concentration of water and decrease the concentration of hydrogen ion. To restore the equilibrium, now more acetic acid will ionize, shifting the equilibrium to the right as you have it written above.






      share|improve this answer








      New contributor




      Charlie Amelotti is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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      $endgroup$

















        1












        $begingroup$

        The hydroxide ion reacts with the hydronium ion (I hate that name; I prefer the simpler "hydrogen ion") to increase the concentration of water and decrease the concentration of hydrogen ion. To restore the equilibrium, now more acetic acid will ionize, shifting the equilibrium to the right as you have it written above.






        share|improve this answer








        New contributor




        Charlie Amelotti is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
        Check out our Code of Conduct.






        $endgroup$















          1












          1








          1





          $begingroup$

          The hydroxide ion reacts with the hydronium ion (I hate that name; I prefer the simpler "hydrogen ion") to increase the concentration of water and decrease the concentration of hydrogen ion. To restore the equilibrium, now more acetic acid will ionize, shifting the equilibrium to the right as you have it written above.






          share|improve this answer








          New contributor




          Charlie Amelotti is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
          Check out our Code of Conduct.






          $endgroup$



          The hydroxide ion reacts with the hydronium ion (I hate that name; I prefer the simpler "hydrogen ion") to increase the concentration of water and decrease the concentration of hydrogen ion. To restore the equilibrium, now more acetic acid will ionize, shifting the equilibrium to the right as you have it written above.







          share|improve this answer








          New contributor




          Charlie Amelotti is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
          Check out our Code of Conduct.









          share|improve this answer



          share|improve this answer






          New contributor




          Charlie Amelotti is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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          answered 2 hours ago









          Charlie AmelottiCharlie Amelotti

          94




          94




          New contributor




          Charlie Amelotti is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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          New contributor





          Charlie Amelotti is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
          Check out our Code of Conduct.






          Charlie Amelotti is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
          Check out our Code of Conduct.





















              0












              $begingroup$

              Zhe's comment is not wrong, but I'd say that your teacher isn't either.



              Consider a 0.1 molar solution of acetic acid. The water will be about 55 molar.



              The twist here is that the proton of the hydronium ion is very liable in water. In other words, the proton exchange between water molecules happens very very fast. That is why using a mineral acid makes a solution very conductive. So just based on chance, a hydroxide ion is more likely to reaction with a hydronium ion than an acetic acid molecule. Hence your teacher's remark.



              However Zhe is correct in that it really doesn't make a difference overall. The H+/acetate/acetic acid equilibrium will be established "fairly" quickly.






              share|improve this answer









              $endgroup$

















                0












                $begingroup$

                Zhe's comment is not wrong, but I'd say that your teacher isn't either.



                Consider a 0.1 molar solution of acetic acid. The water will be about 55 molar.



                The twist here is that the proton of the hydronium ion is very liable in water. In other words, the proton exchange between water molecules happens very very fast. That is why using a mineral acid makes a solution very conductive. So just based on chance, a hydroxide ion is more likely to reaction with a hydronium ion than an acetic acid molecule. Hence your teacher's remark.



                However Zhe is correct in that it really doesn't make a difference overall. The H+/acetate/acetic acid equilibrium will be established "fairly" quickly.






                share|improve this answer









                $endgroup$















                  0












                  0








                  0





                  $begingroup$

                  Zhe's comment is not wrong, but I'd say that your teacher isn't either.



                  Consider a 0.1 molar solution of acetic acid. The water will be about 55 molar.



                  The twist here is that the proton of the hydronium ion is very liable in water. In other words, the proton exchange between water molecules happens very very fast. That is why using a mineral acid makes a solution very conductive. So just based on chance, a hydroxide ion is more likely to reaction with a hydronium ion than an acetic acid molecule. Hence your teacher's remark.



                  However Zhe is correct in that it really doesn't make a difference overall. The H+/acetate/acetic acid equilibrium will be established "fairly" quickly.






                  share|improve this answer









                  $endgroup$



                  Zhe's comment is not wrong, but I'd say that your teacher isn't either.



                  Consider a 0.1 molar solution of acetic acid. The water will be about 55 molar.



                  The twist here is that the proton of the hydronium ion is very liable in water. In other words, the proton exchange between water molecules happens very very fast. That is why using a mineral acid makes a solution very conductive. So just based on chance, a hydroxide ion is more likely to reaction with a hydronium ion than an acetic acid molecule. Hence your teacher's remark.



                  However Zhe is correct in that it really doesn't make a difference overall. The H+/acetate/acetic acid equilibrium will be established "fairly" quickly.







                  share|improve this answer












                  share|improve this answer



                  share|improve this answer










                  answered 2 hours ago









                  MaxWMaxW

                  15.2k22261




                  15.2k22261




















                      Andrew Li is a new contributor. Be nice, and check out our Code of Conduct.









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