This isn’t on topic, but it was so cool I couldn’t help myself. I have a side venting furnace that sends moist exhaust out. There is a metal cap on the end of the vent. That metal is quite cold at the moment (January in CT) and condenses some of the water vapor into water. The water in turn falls on the ground and freezes on the cold driveway. I was going for a walk the other day and noticed the 3 phases or H20 happening right in front of me. Okay, I geeked out, but my question is, is this a physics or chemistry geek-out, or both? Oh, and this video was a couple of days ago. By now the little ice cap on the ground is like a reverse icicle.