when a strong acid is added to a buffer solution, the pH goes down..why? and what bout the base?

Question

Thank you for your help =)

can you explain why it behaves that way by using the Henderson-Hasselbalch equation ( pH = pKa + log [A-]/[HA] ) ?

Answer 1

Provide an example wherein strong acid added to aqueous solution increases the pH. What is an acid and what does pH mean?

Base is then obvious.

Answer 2

You ask for the answer in terms of the Henderson Hasselbalch equation, pH = pKa + log[A-]/[HA]

Add a strong acid: H+ + A- ===> HA (only slightly ionized)
Add a strong base: HA + OH- ===> H2O + A-

So add a strong acid, then [HA] goes up and [A-]/[HA] decreases, the log decreases, and pH goes down.

Add a strong base, then [A-] goes up, [A-]/[HA] increases, the long increases, and pH goes up.

Answer 3

http://en.wikipedia.org/wiki/PH
http://en.wikipedia.org/wiki/PKa
http://en.wikipedia.org/wiki/Buffer_solution

from the links above first understand the matematical definition of pH and pKa then read the link about buffer solutions u ll be able to understand hasselbach then


buffer solution is a solution of weak acids generally, when they added in water they dont dissolve completeley and they come to equilibrium with H atoms so it is not very easy to brak that equlibrium when u use H atoms reaction shifts to products and new H atoms produced. thats why buffer solutions' pH dont change easily