Learn about why bubbles appear in your water overnight; the “other-contingent extravert,” a new type of extravert that’s only outgoing in certain situations; and why food sticks to nonstick pans.
Learn about why bubbles appear in your water overnight; the “other-contingent extravert,” a new type of extravert that’s only outgoing in certain situations; and why food sticks to nonstick pans.
Bubbles in water left out overnight by Ashley Hamer (Listener question from Adam)
This new type of extravert is only outgoing in comfortable situations by Kelsey Donk
Scientists discovered why food sticks to nonstick pans by Cameron Duke
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Find episode transcript here: https://curiosity-daily-4e53644e.simplecast.com/episodes/why-are-there-bubbles-in-my-day-old-water
CODY: Hi! You’re about to get smarter in just a few minutes with Curiosity Daily from curiosity-dot-com. I’m Cody Gough.
ASHLEY: And I’m Ashley Hamer. Today, we’ll answer a listener question about bubbles that appear overnight. Then, you’ll learn about a new type of extravert that’s only outgoing in certain situations; and why food sticks to nonstick pans.
CODY: Let’s satisfy some curiosity.
We got a listener question from Adam, who writes, “When I leave a glass full of water on my desk overnight, I wake up to find countless tiny bubbles along the walls of the glass...I thought that maybe you could help to explain what is going on inside my glass of water overnight! Is the O in my H2O trying to escape?” Great question!
The simple answer is those bubbles are gases escaping from your water. See, oxygen, nitrogen and other gases in the atmosphere can dissolve in water. But how much they dissolve depends on a couple of factors. Temperature is one: gas dissolves more easily in cold water than in warm water. Pressure is another: the higher the pressure, the more gas can dissolve.
Now, think about the difference between the water that comes out of your tap and a glass of water that’s been sitting out all night. The stuff that comes out of your tap is usually cold, because it comes from pipes underground. It’s also pressurized inside those pipes — otherwise it wouldn’t be able to make the journey to your tap. That means that your tap water is chock full of dissolved gases. But as it sits in a glass, the reduction in pressure and the increase in temperature makes the water unable to hold as much of the oxygen and nitrogen that was once dissolved in it. So it comes out — in little tiny bubbles.
You might also notice that the water you left out all night tastes different, too. That’s partly thanks to escaped gases — most likely, chlorine. Many people who grow up with chlorinated tap water learn to associate chlorine with a “clean” flavor, so the less chlorine there is, the dirtier the water might taste. And even though some gases are escaping from the water, other gases from the surrounding air are dissolving in the water, too. But the biggest factor in that stale water taste is probably temperature. The colder a beverage, the less you can taste, so room-temperature water is bursting with flavors that are undetectable when it’s cold. Don’t worry though: water left out overnight is still safe to drink. It just might taste kinda funny. Thanks for your question! If you have a question, send an email or a voice recording to curiosity at discovery dot com, or leave a voicemail at 312-596-5208.
Scientists say there’s a new type of extravert running around. This kind of extravert is only outgoing in certain, comfortable situations. Most of us haven’t been to a party in ages, though, so we’ll just have to take the researchers’ word for it for now.
This group of researchers from Michigan State University felt like they all knew people who were only outgoing or only seemed like themselves in just the right circumstances. And they felt like the usual introvert / extravert binary cut those people out of the mix. They wanted to be able to prove that extraversion has more variety than we usually think.
So the researchers designed a three-week-long experiment involving 83 undergraduate students. To start, the students took a personality test. Then, over three weeks, the students answered email surveys about their social interactions. Twice a day, the surveys asked the students to think about social interactions they had in the previous hour. They rated how friendly and sociable the other person was. Then they rated their own level of extraversion — how talkative, bold, and energetic the students felt during the interaction.
Unsurprisingly, the students tended to be more talkative and bold when the people they interacted with were friendly. But some people were particularly sensitive to others’ friendliness cues in a way that wasn’t related to their level of extraversion. So researchers gave a new name to this flavor of extraversion that’s dependent on others. It’s now called “other-contingent extraversion.”
Now might be a good time to say that extraversion and introversion aren’t terms just invented by Buzzfeed quizzes. They’re real scientific descriptions that date back to the early 1900s. And since the 60s, scientists have been able to detect people’s levels of extraversion and introversion using brain scans. Introverts tend to have thicker prefrontal cortices, which are associated with deeper thought and planning, but also more anxiety and depression. And extraverts have more active dopamine responses in their brains than introverts, so they tend to get more of a thrill from human contact and things like gambling.
Importantly, the researchers on this study found that other-contingent extraversion is distinct from regular extraversion. Someone could be generally extraverted but not be particularly sensitive to how friendly others are being. The researchers think it’s possible that other-contingent extraverts could have more close friends and more enjoyable social interactions. But that’ll require more research — and more time spent outside the house — to figure out.
Nonstick frying pans have ONE JOB: to keep food from sticking. AND YET! Food sometimes sticks to even your best non-stick frying pans. Infuriating, isn’t it? What’s going on? Why does food stick to non-stick frying pans?
This is why. Let’s say you’re gonna fry an egg. You might pour a small amount of oil into the skillet and let it heat up — after all, even nonstick pans need at least a little bit of oil. If you let the pan get a little too hot because, for example, you become totally engrossed in your favorite science podcast, you might notice that the oil in the pan is no longer in one big pool. Instead, it’s formed a ring with a dry spot in the middle.
This happens because of the way the pan heats up: specifically, it creates a temperature gradient where the center of the pan is hotter than the edges. This slight gradient has a huge effect on the oil’s surface tension. In the middle, the hotter oil molecules have trouble sticking together, leading to less surface tension in that area. It creates a surface tension gradient that follows the same pattern as the temperature gradient. Eventually, the oil’s surface tension breaks in the middle and the cooler molecules in the outer edge pull on the hotter ones closer in. That’s what forms that dry spot in the hottest portion of the pan where your eggs are most likely to stick. Physicists call this thermocapillary action.
Believe it or not, this was all discovered pretty recently. A team of Czech scientists heated up some oil on both ceramic non-stick pans and ones with a name-brand nonstick coating. The oil quickly dried up on the hottest part of the pan each time they ran the experiment, no matter what type of pan they used.
So how do you keep your food from completely defeating the purpose of your non-stick pan? Well, the researchers have some advice. Their first tip? Keep the heat moderate. Nonstick cookware manufacturers actually warn against high heat, since the nonstick coating kinda stops working at that point. Their other tip is to use more oil. The thicker the oil layer, the less likely it is to dry up. You can always pour off the excess when you’re done cooking.
Bon apa-heat!
CODY: Before we recap what we learned today, here’s a sneak peek at what you’ll hear next week on Curiosity Daily.
ASHLEY: Next week, you’ll learn about why there’s a good chance your sleep tracker is inaccurate;
What’s up with the animal life scientists found beneath the Arctic shelf;
Why there’s no such thing as a hypoallergenic dog;
The surprising benefits of having a bad boss;
And more! Oh yeah — and, of course, there’s April Fool’s Day…
CODY: Oh, that’s next week? Huh, I hadn’t thought about it. I’m sure we won’t do anything special that day.
ASHLEY: Uh huh.
CODY: But hey, that’s then, this is now! So let’s recap what we learned today.
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CODY: Today’s stories were written by Ashley Hamer, Kelsey Donk, and Cameron Duke, and edited by Ashley Hamer, who’s the managing editor for Curiosity Daily.
ASHLEY: Today’s episode was produced and edited by Cody Gough.
CODY: Have a great weekend, STICK WITH US Monday to learn something new in just a few minutes.
ASHLEY: And until then, stay curious!