Dang. So, for lab #8 of my chemistry class, we reacted some zinc with some iodine and have to write a report for it. Seemed simple enough, and it should be.

Except I have a glaring problem. The amount of unreacted zinc I have left over I weighed to be 0.52g, while the total zinc I had initially was weighed at 0.51g. Which...means I had negative 0.01g of zinc react, and that is very clearly very wrong. I've emailed my TA to see if there's anything I can do about it, because without a proper measurement, I can't do anything for the lab report.

Oh, I did figure out the answer to my molarity problem from before, though. Apparently we're supposed to "assume" we have 100g. Why did high school teach us to never assume?