The objective of this experiment is to;
•Identifying the range and limits of a measuring apparatus.
•Rectifying any instrumental error that might be present in an instrument.
•Investigating the limits and capabilities of a measuring instrument.
•Determining the accuracy of the actual volume of a volumetric pipette, volumetric flask & measuring cylinder.
The purpose of this experiment is to investigate the measurement of the actual volume contents of volumetric glassware. If there is a slight variation in this instrument, it would cause systematic error and thus, the accuracy of results of an experiment or investigation would be affected.
All volumetric glassware has marking on it. It is either being marked with TD or TC, which brings the meaning of ‘to deliver’ and ‘to contain’ respectively. For example, a pipette has a marking of TD, which means a pipette is marked as a ‘to deliver’. Whereas, volumetric flask has TC as its marking, meaning it is marked as a ‘to contain’.
A volumetric pipette & measuring cylinder can be calibrated by just weighing the water they deliver. As for volumetric flask, the weight of an empty flask is recorded. Next, weigh the flask after filling it with water to the mark.
After that, it is crucial to convert the mass to volume. The water density at a temperature will aid this process. The compliance of the Volume Occupied by 1.000g of Water Weigh in Air table is deemed necessary throughout the comparison.
In order to obtain the true volume of volumetric glassware holds, this formula will be used.
This experiment shall be repeated twice more to enhance accuracy of the results obtained. Besides detecting systematic errors, this experiment would aid on the technique and understandings to the correct use of these equipments.
•10ml volumetric pipette
•25ml volumetric pipette
•100ml volumetric flask