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[–] 97 points 8 months ago (23 children)

this feels like a potentially sincere attempt to recruit people into an anti-science conspiracy movement - this doesn't really feel different than the kind of reasoning you see with moon landing denialists or flat earthers.

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  • [–] 116 points 8 months ago* (6 children)

    Eh I wouldn't take it too seriously, I'm pretty sure it's a play on the whole running joke of "saying something ridiculous, then end it with 'You guys don't seriously believe this right?!?'" type of thing. I've seen many of these greentexts that used that format recently.

    It's kinda funny to me because it loosely reminds me of same logic as those old rage comic "troll physics" memes like these:

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  • [–] 16 points 8 months ago (3 children)
  • [–] 48 points 8 months ago* (last edited 8 months ago) (10 children)

    It's actually not a bad question, just one people don't really think about. Why does room temperature water sublimate evaporate?

    It's because the temperature is an average, and some molecules at the surface have enough energy to break their polar bonds.

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  • [–] 22 points 8 months ago (1 child)

    I wanna say Bill Nye had a little contraption that explained this phenomenon. A cup with a piston on one end that vibrated. The top part of the cup had a ring in the center where little balls in the cup could fit. The piston represented the temperature (energy). Even at a lower temperature, some balls could randomly fly into the little hole and into the other partition. Turning the temperature up (increasing the speed and power of the piston) made more balls more frequently "evaporate." I wish I could find that demonstration again.

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  • [–] 78 points 8 months ago* (8 children)

    Enter vapor pressure:

    Basically water always evaporates if the air is completely dry, until the air contains a certain amount of water (measured in partial pressure, which is the part of the air pressure that is caused by water vapor). This partial pressure is temperature-dependent, so if you have 20°C (normal room temperature) you're gonna have 23 mbar of water vapor partial pressure in the air. Source

    So water still evaporates at lower temperatures when the air is dry enough. It's just that at 100°C ("boiling point of water"), that partial pressure of water vapor in the air increases to 1013 mbar which is equal to the total pressure of the air; In other words, at that temperature in equilibrium, the air is totally made up of water vapor and nothing else. If you increase the temperature above that, the water vapor partial pressure tries to still increase, which makes the total pressure go above normal air pressure, which causes a pressure gradient and causes the air to move with mechanical force, which you can use to make turbines spin.

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  • [–] 31 points 8 months ago (2 children)

    A more microoscopic explanation is due to Maxwell-Boltzmann distribution.

    First, you need to underestand temperature. The difference between cold and hot water is the average speed at which particles move, with hotter water's particles moving faster.

    But this is just the average speed, it turns out that particle's speed can be se en as a random variable, and they follow Maxwell-Boltzmann distribution:

    Maxwell-Boltzmann distribution

    So you have a small proportion of particles that move very fast, even in cold water. If some of those particles get (or collide with other particles near) to the "layer" of water that is on contact with the air, they will have enough energy to escape water's superficial tension, thus going into the air and out of the water body. The higher the average speed of the particles, the faster this process will go. Finally, the rate at which this process happens also depends on the energy required to be able to leave the water body, which depends on factors like air pressure.

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    [–] 57 points 8 months ago (5 children)

    Water operates on Celsius so it only needed to be 100 degrees retard

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    [–] 32 points 8 months ago* (last edited 8 months ago)

    matter changes state based on temperature

    This is a gross oversimplification and your experiment proves that :)

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  • [–] 31 points 8 months ago (5 children)

    Water doesn't need to boil to dry out.

    Obviously it's just losing wetness over time.

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  • [–] 27 points 8 months ago

    Anon still lives with his mom and she mopped up the spill.

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  • [–] 24 points 8 months ago (3 children)

    The teacher was explaining about conducting and not conducting, and we had a battery with lamp thing to test on various objects. I of course had to test this on a pencil and discovered semi-conducting. That was a serious "not today" sigh from the teacher.

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  • [–] 9 points 8 months ago* (last edited 8 months ago) (1 child)

    How did that work?
    Doesn't pencil lead material just work as a resistor? It's mostly graphite and clay, and shouldn't have the required structure to work as a semi-conductor.

    Ahh right. I had forgotten about how to term "semi-conducting" was used back in elementary, thanks to semiconductors and the lot.

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  • [–] 19 points 8 months ago (10 children)

    It's interesting because very pure water without asperites can be heated above 100c at standard pressure at sea level without boiling. But once impurities are added to it it starts boiling vigorously!

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  • [–] 11 points 8 months ago (2 children)

    Sounds like the same thing that happens at 0°C with very pure water that stays liquid, but shake it and bam! It insta-freezes.

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    [–] 15 points 8 months ago

    Anon didn't pay attention in physics class.

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  • [–] 15 points 8 months ago (1 child)

    Temperature is based on "average" kinetic energy so technically there are molecules with higher energy's that are higher than the transition state and that's why

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  • [–] 14 points 8 months ago

    For fun I'm going to explain why. So air can hold some amount of water in it at any temperature. Water energy in form of heat is not evenly distributed so some molecules move faster than others, at the surface some move fast enough to escape the water and into the air. That's called evaporation, boiling does however require 100°C.

    This also explains why humid weather affects evaporation (lower capacity to hold water in air) and at high humidity there's an a similar chance of water being deposited to the body of water as water escaping which affects evaporation speed a lot.

    Honestly, I really like this quality of water, it would be super annoying to deal with otherwise.

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  • [–] 9 points 8 months ago

    You claim water boils at 212⁰

    Yet this sponge soaks it right to at room temperature.

    Curious.

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  • [–] 6 points 8 months ago

    "Water can only fly when its a gas!!!" Words from losers that have never looked at the sky.

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  • [–] 6 points 8 months ago (1 child)

    If water turns into gas at 100 degrees, how come I can pour it into a mug?

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  • [–] 6 points 8 months ago* (last edited 8 months ago)

    I had this question in a mid-term in physical chemistry 20 years ago. I can't remember the details but it is driven by the entropy in the system. Along with the things other have said about changes right above the surface of the puffle.

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  • [–] 4 points 8 months ago

    Those are the little water goblins stealing your moisture while nobody's looking.

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  • [–] 4 points 8 months ago

    Water is air soluable.

    It's just like how salt will disappear in water without needing to get hot enough to melt.

    Though both of them still need the thermal energy to do the state change, but they just borrow it from their neighbours.

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