Hello, I’m a higher-level chemistry student and I conducted an experiment with the purpose to determine the pKa of creatine monohydrate through titration curves.
In the experiment, we did an acid-base titration with 0.1M HCL and 0.1M NaOH. We measured 5g of creatine monohydrate using an analytical balance and dissolved it in the HCL then did the titration. We then determined the neutralization point from color changes due to indicator. We did 3 trials with creatine dissolved in HCl, and 3 without creatine dissolved in HCL (titration of HCL and NaOH only).
What is the average uncertainty of the creatine monohydrate mass? And what is the average uncertainty of the neuralization volume? The systematic uncertainties are 0.001g and 0.028ml respectively
In the analysis, we need to plot dpH/dV vs volume of NaOH to find peaks which are the equivalence and half equivalence points. But why is that? Should it be dpH vs volume? And what is the uncertainty of this graph to add error bars and how find it? The uncertainties of pH and volume are 0.043 and 0.028ml respectively. (note (d) states for derivative or change in)
One last thing, it took 9.6ml NaOH to neutralize the solution without the creatine powder and 9.8 to neutralize it with the creatine powder. Why is this? Please include a detailed explanation for this part if you can
Do you think this experiment is solid? What do you think are its limitations other than the systematic errors mentioned?
I would really appreciate answers because I’m kind of lost in all of this. Thank you!