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How to 'identify' Buffer Region? help-

How do i identify buffer region?

what i know: buffer regions can only be formed in the titration curves for: strong acid vs. weak alkali and weak acid vs. strong alkali
why? cause there are two types of buffer solutions.
(1) Acidic Buffer Solution
for formation of this, you need:
(i) weak acid (e.g: X)
(ii) salt formed by the reaction of (X + strong alkali)

(2) Alkaline Buffer Solution
for this you need:
(i) weak alkali (e.g: Y)
(ii) salt from the reaction of (Y + strong acid)

what i understand: Buffer region is where you see very small or no changes at all in the pH when you add small amounts of acid or alkali.

Main Question: so in the image below, why is the buffer region not on the horizontal line (marked in red) ?
why is it on the horizontal line at the beginning of the graph?
20230208_003700.jpg

My reasoning for the question: cause pH is changing slowly at the end of the curve too
(edited 1 year ago)
Original post by Aleksander Krol
How do i identify buffer region?

what i know: buffer regions can only be formed in the titration curves for: strong acid vs. weak alkali and weak acid vs. strong alkali
why? cause there are two types of buffer solutions.
(1) Acidic Buffer Solution
for formation of this, you need:
(i) weak acid (e.g: X)
(ii) salt formed by the reaction of (X + strong alkali)

(2) Alkaline Buffer Solution
for this you need:
(i) weak alkali (e.g: Y)
(ii) salt from the reaction of (Y + strong acid)

what i understand: Buffer region is where you see very small or no changes at all in the pH when you add small amounts of acid or alkali.

Main Question: so in the image below, why is the buffer region not on the horizontal line (marked in red) ?
why is it on the horizontal line at the beginning of the graph?
20230208_003700.jpg

My reasoning for the question: cause pH is changing slowly at the end of the curve too

For there to be an acidic buffer solution, there must be an excess of the weak acid. That means that on a strong base-weak acid titration curve, it cannot be past the vertical section, since by that point, all the acid has been neutralised.
Original post by TypicalNerd
For there to be an acidic buffer solution, there must be an excess of the weak acid. That means that on a strong base-weak acid titration curve, it cannot be past the vertical section, since by that point, all the acid has been neutralised.


thanks! now all the graphs in my notes make sense.

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