Name: 化学者だけど質問ある？ | Tech Support | WIRED Japan
Uploaded: 2025-03-20T10:00:04.000Z
Duration: 14 min
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My name is Dr. Kate Bieberdorf, but you may know me as Kate the Chemist.

Today, I'll be answering your questions from Twitter.

This is Chemistry Support. ["Chemistry Support"] Cy Rehab wants to know, isn't the whole universe a chemical reaction?

If you can see it, breathe it, touch it, it's chemistry.

We're taking atoms and rearranging them into different ways, and it's just chemistry everywhere, everything, everything around us, it's elemental.

Next up, from Enon Yam, wants to know, chemistry lecture, why does Diet Coke and Mentos make a chemical reaction?

Mentos is a porous candy, and so if you look really closely at a Mentos, Mento, Mentos, all of it on the outside has these little holes, there's these little pores, and when we drop it into Diet Coke, that is immediately attractive to carbon dioxide.

So all the carbon dioxide in the soda rushes to the candy, and it starts to sit on those pores, but it's not just one carbon dioxide molecule or a second carbon dioxide molecule, it's hundreds and thousands of them slamming together at once.

So as they reach the candy, they're smashing into each other here, they build up pressure, and they end up shooting straight out of the Diet Coke, and so we have this really beautiful soda volcano.

It has nothing to do with the Diet Coke itself, it's the fact that there's carbon dioxide in the soda, and it's the shape of the candy itself.

So you could do this experiment with Coke, with Mountain Dew, with any soda you want, it just so happens that Diet Coke works really well, and it doesn't contain the sugar, so it's much easier to clean up.

Now HollyJean05 wants to know, in chemistry, how do you get two bonds to break up?

I will say you can get two bonds to break whenever you have neighboring atoms that they are more attracted to.

I don't know if you've ever heard of this, but Blake Lively and Ryan Reynolds, when they were first together, they were set up on blind dates with other people.

And so you have Blake and another man with Ryan and another woman.

And so they're sitting across the table from each other, not interested in their original pairing, very interested in each other.

And so this is referred to as a double replacement reaction, where you start off partnered with somebody else, but then you see something that's better, a better option.

I mean, it's Ryan Reynolds, how can you, you know.

And so now Blake and Ryan are now paired.

And then these other two are not, but in theory, they could be partnered up if they wanted to.

Your atoms are more attracted to something else.

Kick the PJ wants to know, just found out that my brain has chemicals inside it.

You need them, otherwise you're not gonna be able to function at all.

For example, adenosine is in your brain and that helps you get sleepy or drowsy.

So it encourages your body to go to sleep.

You absolutely need these molecules in your brain.

Without them, you would not be a functioning human.

Courtney Neros wants to know, if atoms are primarily composed of empty space, why can't you pass your hand through a solid object?

An atom is formed with a nucleus in the center and in the center, you have protons and neutrons.

So if my body was an atom, my kidneys, my liver, those would be my protons and neutrons, like inside my core.

Now on the outside of your atom, that's where your electrons are moving around.

So that would be like my gloves or my sunglasses or a hat, something that's on the outside.

So atoms can really easily exchange electrons to a neighboring atom.

I can give you my gloves, I can give you my scarf, I can't really give you my kidney or my liver.

So we can exchange electrons, but not so much protons and neutrons.

Now the question here is why can't you pass your hand through a solid object?

And the reason being is because that nucleus is extraordinarily dense.

It's got those neutrons, those protons, and it takes up a lot of space.

And so yes, you can pass your hand through the spot that has all the electrons, but as soon as you slam into that nucleus, that's a dense object that you cannot pass through.

Now we have Carly0575 wants to know how do pheromones work?

So what happens is one animal, let's say you have an ant, is going to release some pheromones.

Then a neighboring ant is going to absorb those pheromones into their body and all of a sudden have all these new signals, some information.

Other animals could possibly give out sex pheromones.

So it's kind of like a way to play Cupid and you can encourage someone else to be attracted to you just by giving those off.

Unfortunately, humans don't have sex pheromones because we learned how to communicate.

So if we just wink and give a little high five, usually that can send the message across.

We don't need to like shove our hormones into someone else to make them attracted to us.

IQ Air wants to know what's in a firework?

It's a combination of potassium nitrate, some carbon and some sulfur.

So essentially what happens is the potassium nitrate decomposes, releasing oxygen gas.

When oxygen is in the presence of charcoal or carbon, it's going to burn and the sulfur helps to create a lot of smoke.

Now there's usually a second piece in there, like a delayed timer that's going on as well.

And so once that gets hot enough, that's going to do the second boom.

So the first explosion gets us all the way up to the sky and the second explosion gives us the huge bang.

So if there's red, there's going to be some strontium in there.

If there's some green or blue, there's probably copper.

The pinks are from potassium, those burnt orange beautiful colors, those are from sodium.

So it's a big mixture of molecules and it's all thanks to chemistry.

Gregory wants to know, does anybody even know what electrolytes actually are or do?

So they're cations and anions in the human body.

So often we see things like sodium, calcium, magnesium, maybe some chlorine, and they all make sure that your body functions properly.

So they're in charge of sending nerve signals through your body.

They're in charge of making sure your heart beats.

Some of them make sure that you have enough fluid inside the cells, while another one makes sure that you have enough fluid outside of the cells.

The chlorine is even used to help digest things in your stomach.

So it's all over your body and you need these electrolytes.

And that's why if you're drinking alcohol, you usually feel like awful the next day because you've pushed all these electrolytes out of your body and now your body is a little bit wonky.

All right, from SciAmerica, what's the chemistry behind home pregnancy tests?

Home pregnancy tests work very similarly to our rapid COVID tests.

So you have a piece of paper and you have an antibody that's essentially sewn into the paper.

So when a woman becomes pregnant, about 10 days after conception, we have this hormone called HCG.

And what happens is you can urinate that out onto your test.

And if that hormone is present in the urine, it will bind to the antibody in the test and it will activate a dye molecule.

And so that's where you'll see that like blue plus sign or the blue word pregnant or anything like that.

Fun fact, like a long time ago in ancient Egypt, they used to use home pregnancy tests by having women urinate on barley seeds and wheat seeds.

And if they sprouted really quickly, that hormone must be present in the woman because that's what activated those seeds and make them sprout really quickly.

So they could actually detect pregnancy with about 70 to 85% accuracy.

Up next, Afstanton asks, what is the most dangerous chemical reaction?

Okay, so you have to be careful because this question would absolutely start a fight with a gigantic group of nerds.

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化学者だけど質問ある？ | Tech Support | WIRED Japan

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