The purpose of the calibration of volumetric glassware is to study the measurement of the actual volume using 3 different types of glassware. The calibration was done by measuring the mass of water contained in (10 ml pipette and 50 ml burette) or delivered by the glassware ( 50 ml Beaker). The temperature was assumed constant during the experiment and it has been used to calculate the true volume from the mass of water. The temperature, mass of water , and mass of containers are measured and recorded Accuracy and precision are important in analytical chemistry lab .According to the results it can be noticed that the calculated volumes were not equivalent to the expected volumes in the three trials. The actual volumes were less than the expected volumes. In other words, the trial results were not accurate or constant. In the first trial a 50 ml beaker was used. However, the relative error is 0.84 %. The beaker was not precise in the experiment, the repeated values of water volume were not equal to 10. All of the values were less than 10 ml. In addition, the experiment was not accurate because none had range equal or above the true value which is 10 ml. In the second trial the 10 ml pipette was used, and it is the most precise instrument between 3 experiments and the relative error of it is 0.29%. Last trial was the 50 ml burette and the relative error is 0.37%. Pipette in this experiment had the highest mean and the lowest standard deviation these results indicated how the results close to the average 9.9710 and the precise of the pipette. The different between the standard numbers and experiments numbers was happened because of the errors. There are some possible random errors such as slight variation in the level of the eye while reading the measurements in the beaker, pipette and burette. In addition, there could be a systematic error such as a problem in the analytical balance. Another systematic error is the density because the density depends on the temperature and in the experiment the temperature was assumed that it is constant, and the water is at thermal equilibrium with the room (lab manual)
To sum up, Calibration of volumetric glassware was conducted to study the accuracy and the precise measurements of the beaker 50 ml , pipette 10 ml and burette 50 ml .The results showed that the experiment with the highest standard deviation was the 50 ml beaker while the lowest standard deviation was 10 ml pipette. were somehow close to the standard number which is 10 ml but they were not accurate or precise because of the errors . Pipette was the most accurate and precise instrument in this experiment.
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