Monday, the first thousand light bulbs

Over the weekend, I took my large syringe to my room at school and calibrated it with water and a triple beam balance. I wanted to see whether or not the markings on the side of the syringe were in fact legitimate. If not, at least I will have measurements so that I know what each gradation actually is. According to http://www.csgnetwork.com/waterinformation.html tap water at the temperature I measured it at, has a density of .99624g/mL (interpolated).

 The slope (also the density) from my data was .9965g/mL accurate to 3 sig figs, so I have no worries about the precision of my instrument.

So today, one of the goals will be to oblige Dr. Rudi and place various building materials in a container with some CO2 and see if there are any changes in that level. Do the building materials exude or absorb the CO2. I expect nothing to happen, but that remains to be seen. I will try to test in the region where our fan will operate, 1000-5000ppm.

• First up: 2 pieces of dry wall about 5" x 26"(unpainted, unplastered)- no appreciable change

• Second: 1 cinder block (new)- CO2 ppm drops more than expected. Must do a more rigorous test. Sealed the entire container with the cinder block and CO2. The CO2 level dropped down from 1200ppm to a lowly 200ppm. The room we are in is at about 800ppm, so there is no excusing the drop in CO2. Upon doing some research, I see that to create lime in cement (and cinder blocks) CaCo3 is heated to 500-600 degrees celcius to create CaO and CO2. This reaction is reversible. Technically, the cinder block is a combination of coal ash, and portland cement, which is 3CaO•SiO2 and 2CaO•SiO2. Perhaps the CaO is being coaxed out of the block. This would eventually reach an equilibrium state, but it could take months for a new cinder block to reach that point. Very interesting, indeed!

• Third: 3 bricks (old)- no appreciable change

• Fourth: 2- 1sq. ft. ceiling tiles- no appreciable change

• Fifth: 1 linoleum adhesive floor tile- 

• Sixth:  3 carpet samples- no appreciable change

• Seventh: 2 small plants (a fern and a caladium)- There seems to be a trend of rising CO2....hmmm. Have I been lied to all my life? I have just been told that plants generate CO2 and O2 in different situations. Does everybody know this? I could swear that my biology teacher said plants make O2 with no mention of CO2 production. What is the net result? Sheesh. Too many variables in this little test.

Later, Dave