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Buffer Solutions


pKa 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




















pKa value of a weak acid with known dissociation constant

Dissociation constant of weak acid : X 10
pKa =
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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
pKa 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
 
Kb value of base: X 10
(or)
pKb value of base:
 
pH =
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Molar ratio of salt/acid required to prepare a buffer of desired pH

Desired pH:
pKa 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)
pKa value of acid in the buffer:
Initial pH =
Altered pH =
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