BobG said:
I loved the labs, but they were definitely an adventure. I still remember the experiment where you put the mystery liquid in a beaker, cover the beaker with tin foil with a tiny pin prick in it, heat the liquid until it becomes a gas, then let the gas condense back into a liquid. Then you had to figure out what the liquid was from it's boiling point and how much liquid you wound up with.
That reminds me of a quantitative chem lab I took. We were given unknowns and needed to do a colorimetric titration. We were told that we should stop as soon as it turned the palest pink. So, that's what I did, got my results, went up to the TA, gave him my results, he looked at it and told me it wasn't right, but there was time to try again. In the meantime, I watched the person who was across from me on the bench turn his solution a dark magenta, get his results, bring them up to the TA, and was told he had the correct values. So, I dragged the TA along to my bench and made him watch EVERY step to find out where I went wrong, because I was positive I had been very careful to do everything right. So, he watched, didn't see anything wrong with anything I did, and the results came out almost exactly the same as the first time. I was convinced my sample was measured incorrectly when it was given to me, but the TA just would not believe me, even after watching everything I did.
I preferred organic chem lab, at least when I had to measure out all my own chemicals to synthesize something, I got reasonable yields and the right product.
Oh, then there was analytical chemistry...ha ha ha...our TA would disappear and attend their department seminar during our lab! There were 12 students in the lab, we each worked with a partner. Each team was doing a different experiment from every other team in the class (6 different pieces of equipment to play with, one experiment for each piece of equipment, and we each started on whatever one we happened to stand in front of the first day of class and rotated through all of them during the semester). So, after the first week, there was at least one group that knew how to use each piece of equipment, and we ended up teaching each other. Though, once we had a problem with a piece of equipment that just wouldn't work right, and out of desperation, we went over as a class to the lab across the hall where we knew another TA worked, and pleaded for him to help us. He was shocked and appalled that our TA had completely disappeared (and he was probably a little bit fearful that a bunch of undergrads were working unsupervised right across the hall from him...we were a bit fearful ourselves). Our regular TA began staying around during the lab after that.
But, to be honest, we actually learned a lot more without our TA...that one was generally useless and when we had to teach each other, we were forced to really learn what we were doing. Oh, but that was also the class where we had to identify an unknown analgesic. For some reason, all the women could identify the tablets based on appearance (even the ones that didn't have "Bayer" stamped across them
)...we weren't supposed to get given the tablets, but I guess our TA couldn't be bothered to crush them to a powder before giving them to us.
Sorry, I'm just reminiscing about chem labs.