Discussion: Average concentration of NaOH solution was 4.35 M. There are many sources of error in this experiment as we got some percentage differences in the two different trials. For the Trial 1 and Trial 2, the percentage difference is 3.7 % which is significant difference to be noted. This percentage difference could occur due to many reasons such as not measuring the KHP properly as we got 0.42 g for first trial and 0.4139 g for second trial of KHP for performing titration but it is more than required value as per literature value is concerned (0.40 g). The almost same percentagedifference occurs for next two trials (1.9 % and 2.5 %). The KHP is always 99.9 % pure, so the titration should give perfect results (Lab Manual). The other possible …show more content…
The 10 mL volumetric pipette is rinse 2 or 5 times to make sure there is no bubble inside because air bubble can cause error in the measurement of concentration because the actual volume of unknown will be less. The accuracy and precision for both sets of experiment was almost same as there were percentage difference of concentrations lies only in 2 % to 4 %. The endpoints of titration for each set of trails in both cases (Part A and Part B) were almost same but there is little difference in volume of NaOH used which cause errors in accuracy and precision of experiment. Using the analytical balance is really careful job as it is most accurate weighing machine with accuracy of 0.0004 g (Lab Manual) and we need to be précised using the balance but some few disturbance can cause big error such as disturbance other students on the shelf it is placed on and not reading the balance properly and taking measurements fastly. Using Volumetric glassware is other method to be more accurate in experiment but there are some possible random error while reading the values such as not reading the lower meniscus of liquid cause error and not removing the air bubble from the burette and using the beaker in place graduated cylinder in case of volume as graduated cylinder is more accurate as compared to beaker (0.02 g) (Lab Manual). Sources of Experimental Error include: The Analytical balance could give wrong reading because of the disturbance due to other students on the shelf it is placed on. Also, taking the reading rapidly and not considering the reading when balance display gets steady. The possible error can occur using wrong glassware like using beaker instead of graduated