For the ninety-nine bad things that happen to me, hopefully once I will be lucky.

Today is that lucky day. I really can't believe I managed to do an external calibration at one go in 2 hours without having to redo the analysis, without having to rerun the calibration, without having to keep aligning the graphite tube.

But after my calculations, my joy soon turned into dread. This is my third time comparing external calibration and standard addition using chicken muscle, and my SA results are consistently half that of EC. Mind, SA is supposed to be more accurate.

My THIRD time. Could it really be that I did something wrong? Something that my mentor wasn't able to identify and thus resort to asking me to repeat and repeat?

Well, I consulted another graduate student, and it turned out that I had made a mistake in my calculations. See, I added 2g of sample solution to 2g of acid and measured the absorbance, so the actual concentration has actually been diluted by half. I can't believe he made me repeat the experiments for nothing!

But oh well... at least there is no major problem...