# Condensation physics question **URL:** \ **Category:** Factual Questions\ **Created:** [April 16, 2010, 4:18am UTC](https://boards.straightdope.com/t/condensation-physics-question/536307 "2010-04-16T04:18:31Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![AllFreedomUnlessDefyingScience](https://avatars.discourse-cdn.com/v4/letter/a/e36b37/32.png) [@AllFreedomUnlessDefyingScience](https://boards.straightdope.com/u/AllFreedomUnlessDefyingScience)\ **Post date:** [April 16, 2010, 4:18am UTC](https://boards.straightdope.com/t/condensation-physics-question/536307/1 "2010-04-16T04:18:31Z")
Since I am a clumsy sort, any drink container on my desk is one with a closable top, to prevent spills (yes like a child, feel free to mock me for it). I recently purchased a new bottle and unlike the old ones noticed an unusual effect. Instead of the plastic bottles I used before, this one was made of aluminum. When I fill it with my cold drink, unlike when I filled the plastic bottles, there is a visible vaporous fog that rises from the mouth of the bottle. I feel certain I would have noticed this before since I have been using the plastic bottles for a long time, and this effect is new to the aluminum bottles. Can someone explain to me whats happening? With thanks, AllFree ---
**Author:** ![pancakes3](https://avatars.discourse-cdn.com/v4/letter/p/ba9def/32.png) [@pancakes3](https://boards.straightdope.com/u/pancakes3)\ **Post date:** [April 16, 2010, 4:32am UTC](https://boards.straightdope.com/t/condensation-physics-question/536307/2 "2010-04-16T04:32:04Z")
the condensation hypothesis is that you work in a super humid place and that the icy drink displacing the air cools the air, forming a minicloud. this has been going on for a while now, and only visible now because the contrast against aluminum is better than clear plastic. if you had colored plastic before then… i don’t know what to tell you. it’s just the fizzy pop of the carbonation? if you’re not drinking soda then i really don’t know what to tell you. i can’t think of anything right now where the aluminum itself would cool the air faster than the plastic. ---
**Author:** ![AllFreedomUnlessDefyingScience](https://avatars.discourse-cdn.com/v4/letter/a/e36b37/32.png) [@AllFreedomUnlessDefyingScience](https://boards.straightdope.com/u/AllFreedomUnlessDefyingScience)\ **Post date:** [April 16, 2010, 4:37am UTC](https://boards.straightdope.com/t/condensation-physics-question/536307/3 "2010-04-16T04:37:39Z")
I was using colored plastic before, although it was translucent, not completely opaque. I’m filling it with Kool-aid, cold from the refrigerator, no carbonation at all. Not only that, while the condensation isn’t a rolling fog like from dry ice, it’s very noticeable, too apparent in my mind for me to have missed it in the colored bottles if it was at the same intensity. One possibility springs to mind, perhaps the difference in rate of heat transfer between plastic and aluminum accounts for it. ---
**Author:** ![Pasta](https://avatars.discourse-cdn.com/v4/letter/p/ecccb3/32.png) [@Pasta](https://boards.straightdope.com/u/Pasta)\ **Post date:** [April 16, 2010, 4:40am UTC](https://boards.straightdope.com/t/condensation-physics-question/536307/4 "2010-04-16T04:40:04Z")
My guess: the aluminum (which is much more thermally conductive than plastic) cools sufficiently above the level of the liquid to serve as a good heat sink for the now swirling air. In the plastic case, only the liquid’s surface could take up heat from the air. ---
**Author:** ![pancakes3](https://avatars.discourse-cdn.com/v4/letter/p/ba9def/32.png) [@pancakes3](https://boards.straightdope.com/u/pancakes3)\ **Post date:** [April 16, 2010, 4:53am UTC](https://boards.straightdope.com/t/condensation-physics-question/536307/5 "2010-04-16T04:53:31Z")
yeah but i’m assuming it’s a travel mug. the inside lining wouldn’t be aluminum too, would it? ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [April 16, 2010, 12:57pm UTC](https://boards.straightdope.com/t/condensation-physics-question/536307/6 "2010-04-16T12:57:22Z")
Can you try pouring into a plastic bottle again, while holding a piece of aluminum foil behind the bottle, or maybe wrapping the plastic bottle in the foil. This would rule out the visibility issue. Otherwise, **Pasta** ’s explanation sounds good. ---
**Author:** ![Quercus](https://avatars.discourse-cdn.com/v4/letter/q/7ab992/32.png) [@Quercus](https://boards.straightdope.com/u/Quercus)\ **Post date:** [April 16, 2010, 6:30pm UTC](https://boards.straightdope.com/t/condensation-physics-question/536307/7 "2010-04-16T18:30:29Z")
Yeah, what Zen/Pasta said, I think the most likely explanations are that you’re just noticing the fog more, or the aluminum’s heat conductivity is to blame. One other remote possibility is that it’s a function of the shape of the container: that somehow the shape of the new bottle mixes the drink and air slightly differently when the drink is poured in, resulting in a larger amount of air that’s just cool and moist enough to fog up. And finally, depending on where you live, it’s also possible that April where you pour your drink is warmer and moister, so more fog-prone (for instance, heating a home often also dries the air, so if the heat has been on steadily but now is off, the house would be moister and more fogable).