OUCC2017HD_Chemistry_Christmas_2018_Transcript
 
[festive instrumental music]

[UW-Madison Marching Band playing "On, Wisconsin!"]

[pressurized spray]
 
[cheers and applause]
- Hello, everyone, and welcome to my lab.

I'm especially pleased that you are here to celebrate this very wonderful anniversary. And I want to thank the UW Band for being here. Weren't they great? 
[audience cheering]

They'll be back, they'll be back. So, thank you very much. I appreciate you being here, and we'll see you shortly. 
[cheers and applause]

It is really special to see everyone and to have you join in this wonderful celebration. Forty-nine years of Once Upon a Christmas Cheery in the Lab of Shakhashiri. It's in the great tradition of the British scientist Michael Faraday, who used to gather young people and their parents and families around Christmastime at the Royal Institution in London and do special experiments for them. Michael Faraday did that for 19 years. I'm very proud that we are doing it now for the 49th time, right here in Madison, Wisconsin. 
[applause]

So I ask you to pay attention because if you pay attention you're going to learn. And I want to make sure that you are really paying attention. What does my T-shirt say?

- Audience: Science is fun.

- Oh, come on, you can do better than that. What does my T-shirt say?

- Audience: Science is fun!

- That's it, we need to have some enthusiasm as we do experiments and as you pay attention. 
[torch flame hisses]
That gets your attention now, right? 
[audience laughs]
This is an example of a controlled combustion reaction.

Just as the flames from the candles are also examples of controlled combustion reactions. Some things burn, but not everything burns. And so what we're going to do now is a series of experiments as you pay close attention to what we have up in the air. What do we have up in the air?

- Audience: Balloons.

- Now, how many balloons are there?

- Audience: Six.

- And are they all the same color?

- Audience: No.

- And what do you suppose we have in them?

- Audience: Helium.

- Some of you are saying helium because you know that helium is a gas lighter than air and I'm going to tell you that it is lighter than air, but it's also a gas that does not burn. So we're going to find out what's in these balloons by bringing this flame close to the balloon. You ready for this? Some of you are covering your ears. Why are you covering your ears? Because you know from experience that there might be some sound energy. We have light energy, we have heat energy. Let's get on with the experiment. 
[balloon pops]

- Audience: Oh!

- So, the balloon popped and that balloon had in it the gas helium. Now what I'm going to do is what we always do in science, repeat the experiment. What color balloon did I ignite?

- Audience: Green.

- All right, we have another green one right here. Are you ready for this? You're paying close attention to it, right? Here we go, ready? 
[pops]

Did the same thing happen?

- Audience: Yes.

- Exactly the same thing? No. The second time the flame went out. That's because I brought the flame closer to the balloon. So those two balloons had in them the gas helium. Now we have another set of balloons here and we have still another set over there. Shall I do more balloons or go on to different experiments?

- Balloons!

- More balloons? All right, let's do this balloon right here. Let's see what happens. You ready for this? You sure you're ready for this? Here we go. 
[explosion booms]
[audience gasps]
 
[applause]

That balloon had in it the gas hydrogen and it's lighter than air, but it combines with oxygen that's in the air in what we call an uncontrolled combustion reaction. You know what's another name for uncontrolled combustion reactions?

- Explosions.

- Explosions. Yes, you're right. What do we always do in science?

- Repeat the experiments.

- Repeat the experiments. Let's do this experiment now in the dark. So, let's try with the lights down. Here we go, you ready for this? 
[explosion booming]
[audience gasps]
[audience cheering]

Did you see that ball of fire? Did it you see it better with the lights on or the lights out?

- Audience: Out.

- Let's watch it one more time in slow motion and see. Well, you won't hear any sound now, you just see that big ball of fire. That's the hydrogen combining with the oxygen that's in the air. You also notice that that combustion reaction released energy in the form of light, but also in the form of sound. And the sound was louder than it was in the case of... ...helium. We have two more balloons on my far right. So, let's walk over there and see if we should ignite those. Should we try to ignite those?

- Audience: Yes.

- But you and I notice that there is a loud sound released, and I want everyone to protect your ears from potential damage. So, take both fingers, stick 'em in your ears. If you can hear the sound of my voice that means you don't have your ears well protected. I can't do that and do the experiment, so I'm going to use this. Right? So make sure your ears are very well-protected as we now reach for this one. Here we go. 
[explosion booms]
[audience gasps]
[enthusiastic cheering]

That balloon had in it a mixture of hydrogen and oxygen. More oxygen inside the balloon than what we have in the air. What do we always do in science?

- Audience: Repeat the experiment.

- Make sure your ears are well protected as we now move over and do this one in the dark, please. The lights down, all the way down. Here we go. 
[explosion booms]
[audience gasps]
[laughter and applause]

Let's have another look in slow motion at the explosive combination of hydrogen and oxygen. You won't hear the sound, but you'll see a much faster reaction that has taken place.

But I'm going to do an experiment with the hot boiling liquid that I have here. The one that I have here is water. I'm going to use my gloves now to protect my hands from heat, and I have some dry ice here, but actually, I'm missing, whoops, I'm missing a dishpan. Let's see if I can find it. Could someone please bring me the dishpan? Would someone please bring me-- 
[audience cheering]
Hello, Bucky.

Good to see you, Bucky, and welcome to my lab. Thank you, this is what I really wanted. So, Bucky, would you like to help me with this experiment? 
[Bucky claps]
 
[audience cheers and applauds]

You notice that Bucky is a good science student. He's wearing his eye protection! I want everyone to see that. And so, Bucky, here's what I'm going to do. I'm going to take the boiling water, I'm going to put it in this dishpan that you brought me.

And what we see coming off the top here, what does it look like?

- Audience: Steam.

- Steam is invisible. You can't see steam. We see a mist. That's what we're seeing: the mist of water vapor. And then, Bucky, here's the experiment. You take this bucket right here and you pour all the dry ice that's in there into the boiling water. Go ahead, Bucky. 
[audience cheering]
Do it, all the way, all the way! 
[audience gasps]

- Whoa! 
[applause]
- That was very, very nice, Bucky. Does that look like steam? No. It is... It looks like fog. It looks like fog and that's what it is. We just made a lot of fog here. You notice that the fog is moving downward now because carbon dioxide gas is denser than air. The condensation is on the carbon dioxide gas that's coming from the sublimation reaction. Bucky, I know you are a very studious student at UW-Madison. I know you are. And now, are you going to-- 
[applause]

How long is going to take you to graduate, Bucky? Let me see that. Up there, I see. Wait, it's going to take you four years to graduate. Wait, you have four. I have five. I guess we are different, yeah. But I'm glad you want to graduate in four years and I know you're very busy now with the final exams coming up and you want to go study, you want to go review, so. So, Bucky, thank you so much for stopping by here. Thank you, very, very, very much for being here. 
[audience cheering and applauding wildly]

- Man in audience: Hey, Bucky!

- I'm going to use these four beakers that have in them the same green-colored liquid and I'm going to add different clear and colorless liquids to them and we'll see what happens. So I'll use this one on my right, on your left, as a reference. I open this container and I add some... household ammonia.
[audience chatters excitedly]
You like that, huh? 
[laughter]

I'm glad you like that. I like that too. Color changes tell us that something is happening and in science, we try to understand what it is that's happening so I take a different clear and colorless liquid now. I add that and...

- Audience: Whoo.

- You get another transformation. Here's a third clear and colorless liquid. What would you predict is going to happen now? Any color change?

How do we find out?

- Audience: Experiment.

- Just stop talking and do the experiment, right? 
[audience laughs]
Here we go. And we can mix those... and we can mix this one too.
- Audience: Whoo.

You notice this one has a solid at the bottom. Let's try to mix it, see if the solid disappears, and we get these beautiful color transformations by adding different liquids that combine with the heavy metal that's in there. The green color is because we have something called nickel sulfate.

These are compounds of nickel that combine differently with the different reagents that we have. So, here's another one that I want to do. I have a beaker. It's empty except for air. It's the same size as the other beakers. 

You're paying attention, right? 'Cause if you pay attention, this is how you learn, and this is how we process information and this is how we start sharing information as we learn from what we have observed and made connections with the experiences that we've had. So, this beaker is empty except for air. 

I'm going to take a clear and colorless liquid and put it in it like so, and then I'm going to put the cap on. Why do I put the cap on? Just in case I knock it down, right? We practice safety all the time. And then I take a clear and colorless liquid and add just a little bit of it and there we go. 
[audience exclaims]

- Oh, you like this one? 
[applause]

Now I want to walk over and do an experiment right here.

Where you see I have a large flask. It's empty. Actually, it's not empty. It has in it a clear and colorless gas.

And it is connected to this large beaker that was water in it. And there is a stopcock here which I'm going to turn and then I'm going to also squeeze this small rubber bulb that has in it just a tiny bit of water.

So, first, I open this and then I squeeze.

[Audience oohs and ahs]

And a small amount of water is dissolving the gas that's up there, the gas is called ammonia. Ammonia is very soluble in water. And then, the pressure in the upper flask gets to be lower than it is, and you see the atmospheric pressure is pushing, is siphoning the liquid up here.

And we put an acid-base indicator-- 
[bells jingling]

- Ho, ho, ho! 
[audience chattering]
 
[audience applauds]
- Hello, Santa!

- Hi, how are you, Professor?

- I am very happy that you're here.

- Nice to be here.

- Did you get my list?

- I got a very long list.

- Oh, it wasn't that long. I've been good. Haven't I been good? 
[audience cheers and applauds]
Did I get anything?

- As a matter of fact, I got you a very special present.

- Oh, thank you, thank you, Santa.

- Is it?

- Keep.

- Open it now?

- Go ahead and open it.

- All right.

- We all want to see what it is, right?

- Yeah, I want to see what it is. 
[audience applauds]

Oh, oh, oh! This was indeed on my list. This was on my list. So, I'm going to open this carefully, like so, and then, I'm going to try to pull it out. All right if I pull it out?

- Yeah.

- Here we go! 

[beads clinking]

- Audience: Ah!

- Isn't that cool? Thank you, thank you, Santa. That, for sure, was on my list. 

Now, in your workshop, Santa, when you and the elves are working hard on all the presents, what else do you do?

- Well, actually, in our spare time and sometimes while we're working, we sing songs!

- You sing songs?

- We do!

- Would you like to sing a song for us?

- I'd be glad to!

- Please.

- So, I'd like to sing a song for you about a young man who has found a young woman and now believes that they're going to be together. This is a song in German because Santa Claus, after all, is German. 
[audience laughs]
Okay.

[blows pitch pipe, sings "Mein" in German]
§ Bächlein 
§ § Laß dein Rauschen sein! § 
§ Räder, stellt euer Brausen ein! § 
§ All ihr muntern Waldvögelein § 
§ Groß und klein § 
§ Endet eure Melodein! § 
§ Endet eure Melodein! §
§ Durch den Hain § 
§ Aus und ein § 
§ Schalle heut ein Reim allein § 
§ Durch den Hain § 
§ Aus und ein § 
§ Schalle heut ein Reim allein § 
§ Die geliebte Müllerin § 
§ ist mein! § 
§ ist Mein! §
§ Die geliebte Müllerin § 
§ Ist mein! § 
§ Ist Mein! §
§ Mein ist mein! §

[audience cheers and applauds]

- What a voice, Santa. Thank you. Thank you so much.

How about asking the audience to join you in singing the song?

- Sure! So, this is such a good time of year for seasonal songs. So let's all sing together a song you all know called “Jingle Bells.”

- Oh!

- Ready?

- All: § Jingle bells, jingle bells 
§ §
 Jingle all the way 
§ §
 Oh, what fun it is to ride 
§ §
 In a one-horse open sleigh 
§ §
 Jingle bells, jingle bells 
§ §
 Jingle all the way 
§ §
 Oh, what fun it is to ride 
§ §
 In a one-horse open sleigh §

- Child: Hey! § Dashing through the snow 
§ §
 In a one-horse open sleigh 
§ §
 O'er the fields we go, laughing all the way 
§ §
 Ha, ha, ha, ha 
§ §
 Bells on bobtails ring 
§ §
 Making spirits bright 
§ §
 What fun it is to laugh and sing 
§ §
 A sleighing song tonight 
§ §
 Oh, jingle bells, jingle bells 
§ §
 Jingle all the way 
§ §
 Oh, what fun it is to ride 
§ §
 In a one-horse open sleigh 
§ §
 Jingle bells, jingle bells 
§ §
 Jingle all the way 
§ §
 Oh, what fun it is to ride in a one-horse open 
§ Sleigh §

[audience cheers and applauds]
- Thank you, Santa, and thank you, audience. You were very jolly. You're always jolly, Santa.

- Of course!

- But did I get any other gifts? 
[audience laughs]

- As a matter of fact, a very special gift.

- Ooh, oh, oh!

- You can play it in your lab--

- Oh! Oh!

- When you've got some spare time.

- Oh, oh! A CD by the Pro Arte Quartet. It is wonderful! They're really my favorite here. Thank you, Santa.

- Santa: And in addition to this, help me to welcome the fantastic Pro Arte String Quartet. 
[cheers and applause]

- Shakhashiri: Oh!

[The Pro Arte Quartet performs "Op.44 No. 2, 2nd movement"]

§ §

§ §

§ §

§ §

[audience applauds]
- Thank you, colleagues from the School of Music. Thank you! Ladies and gentlemen, one more round of applause for the Pro Arte Quartet! 
[audience cheers and applauds]

My next experiment will be done right here where I have a burner and a source of gas. It is propane. I'm going to turn the valve on. 
[scraping spark igniter’s metal]

And now you see the combustion, the controlled combustion of the gas propane. And I have a couple of liquids.

Actually, I have four liquids altogether. And I'm going to take this spray bottle and I'm going to spray into it. 
[audience gasps]
You like that?

- Yeah!

- How about if I use this one? 
[audience gasps]

- Whoo!

- How about if I do both at the same time? 
[audience gasps]

- WHOO! 
[applause]

This color is from lithium chloride dissolved in a little bit of alcohol. This is boric acid dissolved in a little bit of alcohol. This one is table salt, sodium chloride dissolved in the alcohol. And this one is element number 49, indium chloride dissolved in. 
[cheers and applause]
Let's look at those in the dark. So, can you turn the lights down, please? Here's indium.

- Ohhhh!

- Violet, beautiful violet color. Here is lithium.

Here is boric acid.

Here's the two of them together. Isn't that cool? 
[applause]

Actually, it's very hot, not just cool, so... Controlled combustion reactions, once again you see colors that you recognize from the fireworks? The same types of chemicals are used there to generate the fireworks. Well, at this time I would like you to welcome my long-time collaborator and friend, Dr. Rodney Schreiner. Rodney. 
[applause]
Welcome.

- Hello, Bassam. It's a pleasure to be here on this special 49th anniversary of your show.

That's amazing, isn't it? 49 years. 
[applause]

And as a small token of this 49th anniversary, I've brought you a sample of the element whose atomic number is 49.

- So this is the metal indium?

- That's the metal indium, yes.

- Oh, I can bend it.

- Rodney Schreiner: And you can bend it, yes. Indium is a very soft metal. You almost form it into a letter.

- Yeah.

- Yes.

- There we go, yeah. Most of the elements in the periodic table are metals.

- Yes.

- I think about 85% of them are metallic.

- Yes, most are metals.

- And this is safe to handle, otherwise, you wouldn't give it to me?

- That's right. 
[audience laughs]

- Thank you, thank you.

- So indium is a rather rare element though. It's about as rare as silver.

- Shakhashiri: Silver is rare too, right?

- Yeah, silver is quite rare. That's why silver-- One of the reasons silver is valuable is because it's rare. Another reason that silver is valuable is because it is one of the few metals that occurs as a metal in nature.

- By itself?

- By itself. Right, so ancient people knew about silver. They didn't know about indium. So, ancient people thought silver was really valuable and we do too.

- Yes.

- Nobody knew about indium, and so there's poor old indium. 
[audience laughs]

- Is this for me to keep?

- That's for you to keep, yes.

- Okay, thank you, thank you. 
[applause]

- And since we're talking about silver, which is element number 47, just two over from indium, I want to do a few experiments with silver. So, first I have here a solution in this beaker. A solution of silver nitrate. That's silver dissolved in nitric acid. And you can see, it's a clear and colorless liquid like many of the liquids we deal with. And I have three bottles here, also of clear and colorless liquids and I'm going to add them one by one to the silver nitrate. So the first one I'm going to add is a solution of ordinary table salt, sodium chloride. Pour that in.

And you see what happens is it gets cloudy and white. That's because the silver combines with the chloride and forms silver chloride and that does not dissolve in water. That's why it's turned cloudy. The next solution I'm going to add is ammonium or ammonia water. This is like household ammonia. I pour some of that in.

- Shakhashiri: I can smell it.

- Yes, it has a characteristic odor. And when I stir it... Ooh, maybe I need a little more.

- A little more.

- A little more. There we go. That should do it. And the ammonia dissolves the silver chloride and so it goes back to being clear and colorless.

- Almost.

- Almost.

- Right, a little more?

- A little more. You do it.

- More is better?

- Often it is. 
[laughter]

- Sometimes it's just more. So, we'll find out. Okay, here we go.

- Schreiner: There. There. Okay.

- Yup.

- Silver chloride's gone.

- That's good.

- Now I have one more I'm going to add and that is a solution of sodium sulfide. Whoa. I'd say that's black, wouldn't you?

So, here the silver combined with the sulfide and formed silver sulfide. And if you have any silver objects at home, silver metal, this color may be familiar to you.

I'll show you a piece of silver. I have one right here. This is a small silver tray and--- It looks dark.

- Yeah, the color is reminiscent of this because the coating on the silver is silver sulfide.

- So this is what you get when the silver tarnishes?

- When silver tarnishes, yes.

- You get silver sulfide?

- You get silver sulfide.

- Where does the sulfide come from?

- Well, there's tiny amounts of sulfur in the air. Some of it's just remnants from volcanic eruptions. Some of it's from the days when we burned coal with sulfur in it. It takes a long time for it to go away.

- But silver is a nice, shiny metal.

- Right, we don't really like it this way.

- No.

- No, we want it to look shiny.

- Yes.

- So let's see if we can do something about that.

- All right.

- So I'm going to use another metal which is more reactive than silver and you have this metal at home. Here it is.

In all sorts of forms, but this is the one I like. This is aluminum foil. And I'm going to need some more equipment, Bassam. Could you get that pan?

- All right, yes.

- On the back table for me, while I get out some aluminum. Aluminum is more reactive than silver.

So it has a greater affinity for sulfur. Now, what I need to do is to put the silver in contact with the aluminum and I'm going to do it in a dish because I need more than just aluminum.

There it is. Line the dish with aluminum. And then, I'm going to put the tarnished silver dish on top of the aluminum in there. There we are.

Now, they're not going to react just by sitting together. They need to have a liquid around them and I'm going to prepare this liquid. I'm going to use hot water, which I have right here. And I'm going to add another household chemical: baking soda. And I need to dissolve the baking soda in the hot water. And I'm going to need to do this carefully.

Look what happens when you put baking soda in hot water.

- It fizzes.

- It fizzes, yeah.

- Carbon dioxide.

- It's carbon dioxide coming off. So when you heat-- Whoa, I need to be careful! 
[audience murmurs]
 
So when you heat baking soda it decomposes, gives off carbon dioxide. In fact, that's why you put it in cake mixes. When you put it in a cake batter and then you heat the batter, the baking soda decomposes and makes bubbles, but the bubbles don't come out like they do in water. They get stuck in the cake and you get nice, solid foam. Now, I've got hot water and a dish with the silver in it. And I'm going to pour that hot water over the dish. The water's hot so I need gloves. Yes, I will need this too.

- All right.

- And then, you can put that back, okay?

- Okay.

- It's nice having an assistant in the kitchen. 
[audience laughs]

Now I will pour this hot water with baking soda dissolved onto the silver, which is sitting on top of the aluminum.

There we go.

- Shakhashiri: I can see a change.

- And, you know, all good things you have to wait for. So, many of these changes are not instantaneous. You have to give it a little time for the sulfur to become aware that there's aluminum around and for the aluminum to become aware that there's sulfur around, but eventually the sulfur leaves the silver and let's jiggle it around a little bit. There we go.

This one is really, really tarnished.

- Shakhashiri: It is tarnished, yeah, but it looks like an experiment you can do at home.

- Yes, this is definitely something you can do at home, right. You have aluminum foil, you have baking soda, you have hot water, and, if you're lucky, you would even have some silver. Anyway, it's mostly clear. So, here you can see nice, shiny silver.

- Very nice. 
[applause]
Thank you, Rodney.

- It's my pleasure. Absolutely.

- Thank you very much. Thanks, thanks again. All right, for my next experiment, I'm going to mix two liquids in this glass assembly. There's a funnel and there's a receiving vessel at the bottom. And two liquids that I'm going to mix are these two. One is clear and colorless and the other one is clear and blue. And I'm going to do this mixing in the dark. So, would the lights go down, please? Here we go!
- Audience: Oh!

- Oh!

- Yeah! 
[cheers and applause]
- Boy: Oh! 
[audience applauds]

- Shakhashiri: With the lights up, please?

This was the emission of light when chemicals are mixed together. Let's have another look at this in slow motion.

- There, we see the four. And now, we see the nine.

- Audience: The nine!

- Celebrating the 49th anniversary of Once Upon a Christmas Cheery In the Lab of Shakhashiri. 
[cheers and applause]

At this time I would like you to welcome someone who's been working in my lab. Please welcome Julia. 
[applause]
Hi, Julia.

- Hi, Bassam.

- Happy to see you.

- Good to see you, too. How are you?

- I'm fine. What have you been working on?

- Well, I've been doing some experiments with air movement. Air is a fluid and it moves, but everybody knows that, right?

- Yes, yes.

- So, I have here a balloon, and I'm going to blow air, that is, move air into it, and it will inflate. 
[blowing sound]

So you saw that I had to blow harder when I inflated the balloon initially, and then, once I stretched the rubber out it was easier, but you've inflated balloons before, right?

- Shakhashiri: Yes.

- You guys remember that, right? Oh, no! This one has a hole in it.

- It has a hole in it? Oh.

- We better get another one. I need this.

- Well, we have more balloons.

- Okay, we have more balloons.
 
- Yeah. A little too big, I think.

- That's good. So, air movement: you blew air into the balloon, you inflated the balloon.

- Yes.

- You worked harder at the beginning. Everyone knows that.

- All right.

- You tie the balloon.

- You tie the balloon. This one doesn't have a hole in it. Good.

- Good.

- Now, I also have here a hair dryer.

- Yes.

- And when I turn the hair dryer on, a fast stream of moving air is going to come out of the nozzle. 
[hair dryer whirring]

Now, if I take the balloon and do this.

- Whoa, that's cool.

- Yeah, it's suspended in the moving air coming out of the hair dryer.

- So the stream of air that's moving from the nozzle is holding the balloon up there?

- Right, so if I block the air...

- It falls down.

- The balloon comes down. It's pretty cool, huh?

- Yeah, it is cool. 
[applause]

- Now, watch this.

- Whoa. Bravo, Julia.

- Thank you. 
[applause]

[silence]
 
[applause]

- That was really cool.

- Thank you. Now, air movement is what I want to tell you more about. So, I have another experiment that I want to do and I want you to help me with it.

- You want me to help you?

- I do, so.

- I'm ready.

- Here, let's take this and let's move around to the front of the table.

- All right.

- So everyone can see. So, I have a long piece of plastic here and I'm going to give you one end.

- Yes, I can see that.

- I'm going to hold the other end. There's an opening at my end. Is there an opening at yours?

- No, mine is sealed.

- Okay, here, you take this end and I want you to inflate this long tube by blowing into it.

- This whole long tube?

- Yes.

- Just blow air into it?

- Yes, and we're going to count how many breaths it takes for him to inflate it, okay?

- Okay.

- All right. One, two, three, four. Okay, okay, you can stop. I don't want you to hyperventilate.

- Yes, thank you. 
[Julia laughing]

- Let's see how well you did. All right, not too bad, not too bad.

- I tried.

- Yes. Okay, now I want to show you and everyone else how I can inflate this with a single breath.

- Shakhashiri: No way.

- Watch, here you take this end.

- This is the sealed end.

- That's the sealed end. I'm going to take the open end.

Now watch this.

- Whoa. 
[audience cheering]
 
[applause]

- I like that.

- So, what happened is when I blew a stream of air down the middle of the tube it created a partial vacuum around that stream of air and that sucked in more air from around it.

- Huh.

- Would you like to try it?

- Sure, I'd like to try it.

- All right, let's--

- Where are you from, Julia?

- I am from North Carolina. I was actually home-schooled in North Carolina.

- Oh really?

- Yeah. I went to college when I was 11 years old. 
[Julia laughs]

And I graduated from the University of North Carolina- Wilmington when I was 16, with bachelor’s degrees in chemistry and biology. And then I came here to the University of Wisconsin- Madison to enroll in a biophysics graduate program and I got my Ph.D. in 2017 when I was 23 years old.

- Whoa! 
[applause]
- But I want you to try the experiment.

- Well, yes, Dr. Nepper, I will do whatever you want me to do here. So, let's see. I hold this up like this, right?

- That's right.

- And then what do I do?

- Just blow a stream of air down the middle. Okay, now close it off quick. Wow! 
[applause]
Great job, Bassam.

- Thank you so much.

- I love working in your lab.

- Thanks.

- It's so much fun.

- I love having you in my lab, too. Thank you so much. Please give a big round of applause to Dr. Julia Nepper. 
[applause]

My next experiment is going to be done using a very cold liquid.

This liquid is called liquid nitrogen. Liquid nitrogen is kept in a container like this so it remains cold. And I have two other small containers that I'm going to retrieve and use to show you some of the properties of liquid nitrogen.

So, I take the liquid. Ah, it's heavy. I put it in this thermos bottle that's clear.

And you can see the liquid boiling. That's because the glass is at a higher temperature than the boiling point of liquid nitrogen. Liquid nitrogen boils at minus 196 degrees Celsius. Really, really cold. And it continues to boil until the temperature of the glass gets to be the same as the temperature of the liquid. So, we're losing a lot of heat here to liquid nitrogen. We fill it up and one of the interesting properties of this liquid is that you can pour it on, you know, use it for dusting you know, just like that. 
[laughter]
 
It's a very expensive way to dust things. So there are lots of interesting things that we can do. Here is a balloon tethered as you see it. I'm going to pull it down and I'm going to pour some liquid nitrogen. Oh, some of you are covering your ears again. So I add this.
[tsssscccchhhh]

And what's happening? The balloon is collapsing because the helium atoms that are inside are slowing down because of the cold temperature on the outside. I pour the liquid out. It's all gone. And now, as the liquid evaporates, what happens to the balloon?

[crinkling and crackling]
 
[cheers and applause]
It goes up again. 
[applause]

I need a little more liquid nitrogen here. You can see when the cold nitrogen gas comes out we get that condensation again of the water vapor and what I'm going to do next is take one of these chrysanthemums, it's a nice piece of flower here, right? And put it in the cold liquid nitrogen. 
[tsssscccchhhh]

And I'm going to pull it out. It's not as pretty as it was before and it's much more fragile [crinkling and crackling] than it was before. 

- Audience: Oooh! 
[applause]

What I'd like to do now is ask you to join me in welcoming Professor Michael Leckrone. 
[cheers and applause]

Hello, Mike.

- Mike Leckrone: Hi.

- Shakhashiri: Welcome.

- Thank you for having me here.

- Professor Michael Leckrone. Celebrating his 50th year as a faculty member at the University of Wisconsin- Madison.

- Thank you so much. 
[applause]
 
Thank you, thank you! Thank you, Bassam.

- Very, very happy to see you, Mike, thank you. I have a special gift for you to commemorate your visit and it's right there.
- Oh. 
[cheers and applause]

- You see that. That's terrific. It's beautiful.

- And it's made in my lab. It's made of brass. You have brass instruments in the band--

- Most of the instruments in the band are made of brass, right.

- They make beautiful sound.

- They do, most of the time. 
[audience laughs]

- This is for you to keep.

- Oh, thank you so much. What a nice gift. I really appreciate it that. Thank you.

- And in my lab, we work a lot with different chemicals and different metals and sometimes we mix different liquids together and sometimes we get a metal. In fact, I would like to do an experiment with you if you're okay with that.

- I suppose I should put on some goggles.

- Yes, you should put on your goggles, yes. We always obey the safety rules in my lab. Thank you, Mike, for remembering that. So, what we have here. 
[audience laughs]

He still looks the same, right? Give Mike a big hand. 
[cheers and applause]

So, Mike, if you put the gloves on, I will also put this pair of gloves on because we have these round bottom flasks and we are going to empty the hot water that's in them into this bucket right here, okay? So, if you pick one up, use both hands, okay? And then, and then just empty the water just like that. Glug, glug, glug, yeah.

All that way, all the way. Yeah, yeah, you got it. And put it back on the cork, and I will get this out of the way. And then, we're going to mix different chemicals in there.

You have a small flask as I do here, right?

- Yes.

- And you have a big beaker, as I do also.

- I do that.

- All right, we take the big beaker first.

- Okay.

- All right? We put that in there.

A clear and colorless liquid, all the way. And then, what's in the small flask, also a clear and colorless, but different liquid, we put that in. And then we reach for the rubber stopper. We put the rubber stopper on tight and we start mixing. You know, for a chemical reaction to take place we have to mix the chemicals. So... We're getting a dark color. Are you getting a dark color?

- Yes, it is, it's dark. Darker, and I can see myself in it now.

- I can see myself here, too. So this is what we're doing here, Mike. We mixed liquids together and we're depositing a nice thin film of silver on the inside of each of these two flasks.

- Michael Leckrone: We have a new Christmas tree ornament. 
[audience laughs]

- Bassam Shakhashiri: It is the season. 
[cheers and applause]

Yours looks shinier than mine. You did a much better job mixing the two liquids together. And so, here's what I would like to show you.

- Audience: Oooh! This was prepared earlier and, of course, Mike, look what it has on it. 
[cheers and applause]

- Mike Leckrone: I like that. I like that a lot. 
[cheers and applause]

- Well, you know what? We're going to specially treat this on the inside and give it to you as a gift. You can hang it in your office.

- Oh, how nice, thank you.

- Whenever you like. So, Mike, I have another special gift for you. It's this plastic tube. It's sealed. Could you just bend it a little bit? Bend it some more. 
[snap]

- Whoops.

- Yeah, yeah, shake, shake. Now shake it. Ooooh! That matches your jacket here, yeah, yeah?

- You know, I can probably conduct a band with this. 
[audience laughs]

- Shakhashiri: All right.

- Mike Leckrone: Come out here. Come out here, band. 
[cheers and applause]

Let's try and see if the audience can sing along with this one. Here we go, one, two, ready and... 
["If You Want to Be a Badger"]

[drumroll]

- Band: Ah... How do you like me now?

§ §

[audience applauding]

- Shakhashiri: Thank you very much, Mike. Thank you very much.

- Leckrone: I thank you so much.

- Congratulations on 50 years of wonderful community leadership. Thank you, Mike Leckrone and the UW Band!

- My great pleasure. My great pleasure.

- Thank you very much.

- Thank you.

- Thank you. 
[cheers and applause]

The next experiment I'm going to do is one using these plastic bottles that I have here. I have one that I want to show you that has nails stuck on the inside. Actually, they're screws, they're not nails. And this cutaway shows that the screws are separated by a distance of about half a centimeter. So they're not touching. And the other two have the same thing inside, but I want to show you that I'm using a device [electric sizzle] that generates a spark. It's called a Tesla coil. And here's the spark. 
[electric sizzle]

You can hear it, but you can't see it. I'm going to try to show it to you by touching one of the nails and with the lights down, let's see if we can see it. 
[electric buzz]

Okay, hang on. 
[electric buzz]
There, can you see the spark jumping across the gap? With the lights up a little bit. 
[electric buzz]

Now you can see it, right? Now you can see it from the tip of the Tesla coil. All right, so, what I'm going to do now is touch one of those screws and see if I can make that spark jump across the gap that separates them, and we'll see what happens. You ready for this? Here we go. 
[buzz] 
[boom]
[startled gasps from audience]
 
[nervous laughter]
That caught your attention, right? 
[applause]

Here's another one. 
[electric buzz]
[loud boom]
 
[surprised exclaims]
 
[laughter and applause]
- Audience: Whoa!

- You ready?

- Yeah.

- I'm ready. 
[electric buzz]
[boom]
[shrieks of surprise]

- Audience: Whoo! 
[applause]
 
[audience murmurs excitedly]
 
[audience laughs]

- Audience: Whoa! 
[electric buzz]

- Here we go. 
[boom]
[startled exclamations from audience]

You have been a great audience and I want to thank you for coming here to share in the joy of science, the joy of the arts, and to be enjoying whatever else you do when you do experiments. Thank you very much for coming to this special celebration. I want to invite all my coworkers to come out. C'mon! 
[UW-Madison Marching Band plays "On, Wisconsin!"]
 
[clapping to the song]

[audience cheering]
 
[applause]