Molten Mixtures

12/7/12-12/14/12

Though Heather was still in San Francisco, Daniele was at the lab and told me about the conference. She had presented to an overwhelming 20,000 scientists at the conference and luckily it had gone well. Daniele and I spent the day taking the capsule out of the furnace that we had put in last week and extracting the sphalerite and sulfur. When we took the capsule out of the furnace, the molten sulfur-sphalerite mixture was a glowing red. Daniele explained that the previously yellow chunk of sulfur turns red when it reaches molten temperatures. After the capsule had cooled, Daniele and I used a hammer to break the glass of the capsule. The popping sound we heard when we broke the glass confirmed that our vacuum within the capsule had remain intact. The sulfur and sphalerite had returned to their previous yellow color so I worked to recycle some of the sphalerite on the no longer molten mixture. I scraped the sphalerite from the sides of the capsule and put it in a container to use in our next trial of experiments.We removed the chunk of sulfer (which the sphalerite molecules had hopefully diffused through) which Daniele will take to Albany to analyze.

The next week Heather had returned from the conference. Heather decided that today would be a good day to find the hotspot of the furnace we had fixed two weeks previously. The hotspot is the area of the ceramic tube within the furnace that reaches the highest temperatures. All of the experiments should take place at the hotspot for consistency and so that the experiment receives the maximum temperature. The experiment is always lowered into the ceramic tube with a thermocouple to measure the temperature so to find the hotspot, we measured the temperature within the ceramic tube every 0.5 centimeters using the measurement markings on the thermocouple. Though it was time consuming to go centimeter by centimeter, waiting for the temperature to regulate at each new location, we finally found the area where the temperature peaked. Measuring the hotspot took up most of the time we met, but we had enough time for me to make a capsule on my own. Luckily, this time I did not send any flaming glass flying across the lab and successfully made my very own capsule assistance-free. We placed the capsule with the sulfur and sphalerite into the furnace at the newly-found hotspot and then headed into Daniele's office to look at some data. Daniele showed me graphs from her previous experiments with sulfur diffusion. Though the programming tools used to make the graphs showing the sulfur diffusion are still a little mystifying to me, Daniele said that second semester would focus more on organizing the data we have collected from our capsules. Hopefully practice will make perfect and I will be able to figure out the programming!