Volumetric Glassware
Experiment 1: Calibration of Volumetric Glassware
Introduction:
Volumetric glassware is used to accurately measure volumes. Despite all of the tools and instruments available for the use of measuring values of various data, it is impossible to measure the true value of anything. This experiment is intended to develop a person’s capacity to handle volumetric glassware. One must understand how to handle volumetric glassware to acquire the best possible data from the equipment used in lab. Although the instrument may measure a given sample, the value may need to be altered due to various conditions. However, with practice and experience, we can reach very close to the true value, gaining the ability to measure with both high accuracy and precision. The objective of this experiment is to calibrate a 50-mL burette and other volumetric glassware by calculating their correction values. By doing so, we can correct systematic errors caused by the burette’s or glassware’s tolerance values.
Theory1:
Volumetric glassware is used to accurately measure volumes. In any given experiment, students may come across systematic errors or random errors. Random errors are not able to be corrected by a standard mean because they are not consistent. However, systematic errors are consistent and is able to be detected which allows students to correct the error that was found. So, using uncalibrated glassware will cause a systematic error. This error occurs because the volume reading given by the glassware is slightly different than the actual volume that is obtained in the glassware. In order to avoid systematic error, it important to calibrate the measuring instrument so that there is a standard value for zero which allows the measurement to be more accurate.
Calibration of volumetric glassware such as burette is carried out by weighing the amount of water delivered. The temperature of the water used in the calibration must be known since the density of water changes. The
Introduction:
Volumetric glassware is used to accurately measure volumes. Despite all of the tools and instruments available for the use of measuring values of various data, it is impossible to measure the true value of anything. This experiment is intended to develop a person’s capacity to handle volumetric glassware. One must understand how to handle volumetric glassware to acquire the best possible data from the equipment used in lab. Although the instrument may measure a given sample, the value may need to be altered due to various conditions. However, with practice and experience, we can reach very close to the true value, gaining the ability to measure with both high accuracy and precision. The objective of this experiment is to calibrate a 50-mL burette and other volumetric glassware by calculating their correction values. By doing so, we can correct systematic errors caused by the burette’s or glassware’s tolerance values.
Theory1:
Volumetric glassware is used to accurately measure volumes. In any given experiment, students may come across systematic errors or random errors. Random errors are not able to be corrected by a standard mean because they are not consistent. However, systematic errors are consistent and is able to be detected which allows students to correct the error that was found. So, using uncalibrated glassware will cause a systematic error. This error occurs because the volume reading given by the glassware is slightly different than the actual volume that is obtained in the glassware. In order to avoid systematic error, it important to calibrate the measuring instrument so that there is a standard value for zero which allows the measurement to be more accurate.
Calibration of volumetric glassware such as burette is carried out by weighing the amount of water delivered. The temperature of the water used in the calibration must be known since the density of water changes. The
References: 1. Harris, C. D. Exploring Chemical Analysis, 5th edition; W.H. Freeman and Company, New York, 2013; pp 55-71.