Buffer Solutions

Buffer Solutions

pK_a value of a weak acid with known dissociation constant
pH value of a salt/acid buffer system
pH value of a base/salt buffer system
Molar ratio of salt/acid required to prepare desired pH
Components of a buffer solution to yield a specific volume
Change in pH with addition of an acid or base

pK_a value of a weak acid with known dissociation constant

Dissociation constant of weak acid :	X 10
pK_a =
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pH value of a salt/acid buffer system (Buffer equation for weak acids)

Molar concentration of salt:	M
Molar concentration of acid:	M
pK_a value of acid:
pH =
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pH value of a base/salt buffer system (Buffer equation for weak bases)

Molar concentration of base:	M
Molar concentration of salt:	M

K_b value of base:	X 10
(or)
pK_b value of base:

pH =
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Molar ratio of salt/acid required to prepare a buffer of desired pH

Desired pH:
pK_a value of acid:
Molar ratio of salt/acid =
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To calculate the amount of components of a buffer solution to yield a specific volume

Molar ratio of salt to acid:	:
Total buffer concentration (mol/L):	X 10
Gram molecular weight of salt:
Gram molecular weight of acid:
Volume of buffer solution to be prepared:	ml
Quantity of salt required (g/L)=
Quantity of acid required (g/L)=
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To calculate change in pH with addition of acid or base

Molar concentration of salt in one litre of the buffer solution (M):

Molar concentration of acid in one litre of the buffer solution (M):

Molar Concentration of

base

acid

to be added (M)

pK_a value of acid in the buffer:

Initial pH =

Altered pH =