(digital whooshing) - Hey kids, I'm about to show you the coolest thing you've ever seen.

I'm talking, really cool.

I'm about to show you the coolest thing, any of you will ever see in your entire life.

Hi, my name's Sean, with the Museum of Discovery, and today, I wanna talk to you about liquid nitrogen.

Now, normally when you see nitrogen, it's in a gas in the air, you breathe it out every single day of your life.

In fact, there's nowhere on Earth that is cold enough that liquid nitrogen can exist naturally, not even Antarctica.

That's why we have to keep it inside of this special container.

Now, when we talk about solids, liquids, and gases, it's a great thing to use to help illustrate that, because this liquid nitrogen is so cold, it's -321 degrees.

That is really cold.

(children laughing) Now, the way that solids, liquids, and gases work, if you think about an ice cube.

An ice cube is solid, you can touch it, you can hold it, it's very firm.

If you let that ice cube get warm, it's going to melt, and it changes into a liquid.

If you leave that liquid for long enough and allow it to heat up, it's going to evaporate and become a gas and float off into the air.

Now, if you catch that gas and get it cold, it's gonna change back into a liquid.

If you collect that liquid and get it cold enough, it's gonna change back into ice or a solid.

And since this liquid nitrogen is so cold, it allows us to do that very quickly.

Now, as I pour this out, you're gonna notice it kind of looks like water, but I promise you water does not act like this.

You can see how it's trying to jump right out the top of our beaker right here.

Perhaps you've seen water do that before.

If you get water hot enough, it will start to boil, and that's what our liquid nitrogen is doing right now.

It's so warm in this room that that -321 degree liquid nitrogen is boiling, it's evaporating, it's changing back into nitrogen gas.

With it being this cold, it helps to speed the freezing process.

Have you ever had one of these fun, fruity treats in the summertime?

There's nothing better in the summertime than a nice, frozen treat.

But these freeze pops, well, they don't come frozen.

You have to put them in the freezer and then you have to wait.

Sometimes it can take up to six to eight hours for these to freeze.

I don't wanna have to wait that long.

If only I had some liquid nitrogen.

We'll put that in there, and in seconds, it's going to freeze.

But even that is too long for me.

I've been doing all this cool science stuff, I kinda get hungry.

So I brought another treat, this is a Cheeto.

Now, if we put that inside of our liquid nitrogen, it's gonna get really, really cold, as well.

You would never wanna put liquid nitrogen into your mouth, but after just a couple of seconds, all that liquid nitrogen evaporates, I can eat that Cheeto safely.

(children laughing) It's just really, really cold.

Ooh, and pretty cheesy.

Now our little fruit treat, you can see after just a little bit of time inside of our liquid nitrogen, solid as a rock.

Now, that's so cold right now, I wouldn't wanna eat that, so I'm gonna put it off to the side.

'Cause I want to show you one more thing with this.

Now, when it's in its liquid form, it doesn't take up as much space.

But if we were to turn all of that back into nitrogen gas, that'd be very, very impressive.

So we're gonna take it and put it inside of another container, because here in just a second, I'm gonna add boiling hot, 212 degree Fahrenheit water to our liquid nitrogen.

That's a difference of over 500 degrees.

When I do that, all of this liquid nitrogen's instantly gonna change back into a gas.

It's gonna take up too much space to stay inside of our container, and you watch and see what happens.

All right, boiling hot water and science in three, two, one.

- [Children] Yay!

(children cheering) - Well, there you have it, at -321 degrees Fahrenheit, I would say, "Liquid nitrogen is the coolest thing you will ever see."

Thank you so much for tuning in.

From the Museum of Discovery, I'll see you next time.

The Museum of Discovery is a science and technology museum, filled with hands-on, interactive exhibits, perfect for people of all ages.

We hope that you'll come down and check us out.