Thermometer
We wisely opted to paint the floor of Heather's studio with oil-based paint. Which meant that we had to clean our brushes with mineral spirits. I emptied a coffee can into a baggie and used the empty can to rinse our tools and fingertips. Because it took us a week to paint it (each coat took 24 hours to dry, and it took 4 coats), we've had the can full of milky solvents for a while now.
What's interesting is that the vapor above the polluted liquid in the can must expand and contract within the exact same temperature range as our loft. About fifteen minutes after we give up on layering and turn on our expensive heat, the can makes a distinctive "bloop" popping sound. It makes a similar sound 20 or 30 minutes after we turn of the heat, as the can contracts. Like clockwork.
how fun! i can just imagine the anticipation of the pop.
you've discovered the low specific heat and high vapor pressure of organic solvents. the low specific heat allows the liquid and gas temperature to fluctuate with the temperature of the apartment with ease (as opposed to water with its brilliantly high specific heat which lags whatever temperature the apartment is at by many hours). the increase in temperature causes three things:
1) the liquid will expand
2) the amount of gas increases (like steam when boiling water)
3) the gas will have more kinetic energy (like little kamakazi planes attacking the sides of the cans with more and more force)
PV=nRT (pressure x volume= moles x gasconstant x temperature). so you are increasing both T (the temperature) and n (the numbers of moles of gas you have), causing an explosive growth of either pressure or volume. since it is a contained system, the volume stays the same and pressure rises. eventually the pressure rises to the point that it distends the cap, causing an increase in volume until the pressure and volume have reached a happy consensus with one another. some of the pressure will also be relieved in making that satisfying POP!
Aaron has belabored the explanation to the point that even I would be proud! That said, it is the fact that the volume of gas expans and contracts a lot with a little temperature and this is flexing the can and making it pop. It will eventually cease to make noise as the metal fatiques. Bye-the-bye...I'd like to see a good rendition of the new floor.
that just made me really crave the smell of mineral spirits....
I love the smell of solvents too. So does my mom, so maybe it makes sense.
I've used them all and know them all be scent (don't worry, it's a product of my education, I was a printmaking major).
Xylene is my favorite. That, or Hancolite, which has been scarce for years (though a litho professor of mine kept a 5 gallon can of it squirreled away under his desk).
A.
I am sure mick is the ultimate expert on the wonder of organic solvents, I want to hear his tales :)
I remember my days in orgo lab, I had a little trick - I used to keep a flask of acetone on my bench near my hood at all times, so in case I got a whiff of something particulary nasty, I could grab the flask of acetone and it would clear it right out, as well as resurface the memories of my mom with an aqua-green foam toe-separator wedged between her digits, wetting cotton balls with an upside down bottle of rite aid nail polish remover while watching days of our lives.
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