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1.
2.
Explain the plot of pH vs. volume to show buffering capacity of a solution.
Graphically represent the difference between a buffered and
un-buffered solution.
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Henderson–Hasselbalch: Used to prepare buffer solutions and to estimate charges on ionizable species in solution, such as amino acid side chains in proteins
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Determining Buffer Capacity Lab,
Introduction and Background
We will be comparing pH changes of a buffered vs. un-buffered solution.
Normally buffering capacity is calculated using the Henderson–
Hasselbalch equation:
“Used to prepare buffer solutions and to estimate charges on ionizable species in solution, such as amino acid side chains in proteins”
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Determining Buffer Capacity Lab,
Objectives
I. Explain the plot of pH vs. volume to show buffering capacity of a solution.
II. Graphically represent the difference between a buffered and un-buffered solution.
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Determining Buffer Capacity Lab, Tips
Read all procedure and double check with partner.
Carefully count drops dispensed from
NaOH.
Volume NaOH is additive, so amount should increase in table with each drop
If unsure ASK!
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Find another group and compare your buffered and un-buffered graphs to their.
Do you have similar shaped graph, if no how do they differ.?
Are your buffering capacities with in 10% of each other? If no, purpose one (1) reason why.
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