Lab Manual: Buret Preparation and Calibration
Buret Preparation and Calibration
(I) Ratio (mL/drop and drops/mL)
(II) Buret Calibration
(III) Eppendorf Pipet Helper
INTRODUCTION & THEORY
Various apparatus are used in chemistry laboratory.
Most, if not all, can be used for qualitative purposes
(e.g., beakers, Erlenmeyer flasks, syringe, balance, thermometer, pH meter, etc.).
Many of them, however,
can also be used for quantitative measurements (e.g., volumetric flasks, pipets, pH meter, and various
expensive high precision instruments).
It is important and often time saving to know when a rough
estimate is sufficient and when precision is required.
No matter how “precise” an apparatus claims to be, there is no way one can completely avoid the random
or indeterminate (as oppose to systematic or determinate) error.
Thus, what one needs to do is to know the
proper way of using the apparatus and how many significant figures it provides.
Often a carefully devised
calibration scheme must be performed so that the “tolerance” of the equipment is determined.
Chem 100A experiments involve using several precision apparatus.
For this experiment, it will be divided
into three parts,
In Part I, buret will be used to obtain two simple numbers (i.e., volume per drop and its reciprocal).
These numbers (individually measured or collectively gathered) will be used as examples to study how
experimental data can be examined statistically using a spreadsheet.
The method used here will be
applied more or less to many of the following experiments.
Furthermore, this number (i.e., volume per
drop or its reciprocal) may come in handy when doing one of the subsequent experiments.
In Part II, we will focus on the proper usage of the buret (e.g., how to handle it, clean it, read it, take
care of it, etc.) and most importantly, how it can be calibrated via mass weighing of water.
micropipettes commonly used in the laboratory often have to be “re-calibrated” by user or service
The method used here is essentially the same as the one used in re-calibrating
Part III involves an exercise on using a pipet to transfer solution.
Before doing this experiment, you should go to WebCT
Buret Preparation & Calibration and download a copy of the pre-formatted spreadsheet and paste it in your