formula for calulating pH of a buffer?

Question

anonymous · Answer

the pH of a buffer solution containing both acid and conjugate base? Dissociation constant definition 1.1 can be rearranged into

anonymous · Answer

can you please give me both?

anonymous · Answer

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anonymous · Answer

This is so called Henderson-Hasselbalch equation (or a buffer equation). It can be used for pH calculation of a solution containing pair of acid and conjugate base - like HA/A-, HA-/A2- or B+/BOH. For solutions of a weak bases sometimes it is more convenient to use equation in the form

anonymous · Answer

attachment

anonymous · Answer

do you want the calculator

anonymous · Answer

Ca (M)	buffer pH found with the pH calculator

0.1	4.76

0.01	4.76

10-3	4.79

10-4	4.95

10-5	5.47

10-6	6.31

10-7	6.89

anonymous · Answer

@abayomi12  so if i had a buffer that was a weak acid and a salt.. it is which equation?

anonymous · Answer

We'll take a mixture of ethanoic acid and sodium ethanoate as typical.

Ethanoic acid is a weak acid, and the position of this equilibrium will be well to the left:

Adding sodium ethanoate to this adds lots of extra ethanoate ions. According to Le Chatelier's Principle, that will tip the position of the equilibrium even further to the left.