CL-10 Plus – User Manual
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ECPUS vers 0.2 eng
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The Buffer Power.
Buffer is an aqueous system that tend to resist to pH changes, once small amount of
acid (H
+
) or base (OH
-
) are added.
A buffer system consists of a weak acid (proton donor) and its conjugate base (proton
acceptor), as for example the acetic acid form and acetate form.
The
“Buffer Capacity”
is defined as:
∆
H
+
(H
+
concentration)
β
= ------------ = --------------------------
∆
pH (pH variation)
in which the
∆
pH is the pH increment induced by the addition of an amount of base,
whereas
∆
H
+
is the relative change of free H
+
in solution. A large
“Buffer Capacity”
of
the medium corresponds to a large amount of base required to achieve a small change
in pH.
BUFFER POWER measurement, using CL-10 Plus instrument.
The working buffer, using CL-10 Plus, must provide a known and constant Buffer Power.
Sensitivity of the method depends on sample volume, stoichiometry and Buffer Power.
Sample:
HCL 100 mM
Buffer Solution:
Total Acidity
Stopper:
volume of 1225
µ
L
Temperature: 37°C
Micropipette:
Gilson Microman M25
Sample Volume:
10
µ
L
