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Sublimation

Sublimation. The change of a substance from a solid to a vapor without ever becoming a liquid. What the heck is sublimation?. The textbook uses an example of a shirt, drying in freezing temperatures. Dry ice turning to fog is a good example. That’s the background for the last slide.

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Sublimation

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  1. Sublimation The change of a substance from a solid to a vapor without ever becoming a liquid.

  2. What the heck is sublimation? The textbook uses an example of a shirt, drying in freezing temperatures. Dry ice turning to fog is a good example. That’s the background for the last slide. • But laundry here doesn’t dry, so that’s a bad visual. • If you’ve never seen dry ice, your homework is to find a video of it freezing something. Dry ice bubbles are also cool.

  3. Science of sublimation As to not bore you, I’ll keep this short. Also, the textbook was really lacking on this topic. Basically, in non-science-y terms, when something goes from frozen to dry without becoming wet, it’s gone through sublimation. • A Key Thing The Textbook Suggests You Remember: Sublimation occurs in solids with vapor pressures that exceed atmospheric pressures at or near room temperature.

  4. Psychology of Sublimation • In psychology, sublimation is an mature technique where publicly improper impulses are transformed into generally acceptable behaviors. Sigmund Freud said this was an indication of maturity, allowing people to act “normal” in culturally acceptable ways. • This isn’t at all related to the chapter, I just thought it was interesting.

  5. Uses for sublimation (that we might actually use) • Freeze-drying: Freeze a liquid, then use a vacuum pump to suck out all the water vapor. That’s how they get freeze-dried ice cream. (Can be found at camping supply stores, very yummy!) • Shipping frozen things: Dry ice sublimes, therefore it doesn’t melt like ice and leave water all over the place. • Separating substances: Organic chemists use sublimation to separate mixtures and purify compounds. Okay, so maybe we won’t use this one as much…

  6. So What? • Sublimation isn’t just one of those things that’s taught but never used. I mean, if you like your ice cream melted or your compounds impure, fine, I don’t care. • We use it in everyday life, and it’s pretty simple. If it’s solid, and then it disappears without ever making a puddle, it sublimated. • And now, if you haven’t fallen asleep, I’ve succeeded in presenting “SUBLIMATION!!!”

  7. The End

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