Balloons
In this clip, scientists show the students the Alkali Metals; Lithium, Sodium and Potassium, reacting with water. After watching the clip, learn how to relate reactivity to the numbers of electrons in outer shells.
Video Player Keyboard Controls
Play/Pause: Space
Fast Forward: Right Arrow
Rewind: Left Arrow
Video Transcript
Narrator
Hydrogen and helium.
Peter
These two elements make up 99% of the Universe. These were formed right at the beginning of the Universe in the "big bang".
Narrator
And a big bang is exactly what the kids are about to get. Hydrogen and helium are the two key components that make up the sun. The nucleur fussion of hydrogen into helium generates the suns energy. Peter wants the kids to experience both gases for themselves, but he's taking a big risk.
Aimee
In my science people, like, don't do any experiments because people mess around all the time.
Tammy
We don't do many experiments in school because we can't behave properly.
Narrator
But Peter has to put his trust in the kids if the project is to succeed. Just as it's about to get interesting, Sadie finally puts in an appearance.
Peter
Nice to see you Sadie, how come you're late?
Sadie
I'm late because I went dentist.
Peter
Dentist? Ok well I wasn't told about this. We need to get you a lab coat we're about to do an experiment ok. Ok can you put your lab coat on please Sadie.
Narrator
Before letting Sadie and the others loose on hydrogen, the most explosive gas in the Universe, Peter wisely decides on a trial run.
Peter
And what element is in your balloon?
Students
Helium.
Peter
Please don't set fire to anything except the balloon. Paul please hold it out like that please.
Narrator
But once Peter's confident the kids will behave, the fun really starts.
Peter
Now this one is dangerous and is very different from the helium. These balloons are hydrogen balloons. I'm going to show you now then why people do not fill their party balloons with hydrogen.
Narrator
When it's mixed with air, hydorgen becomes incredibly volatile. At last Peter's got the kids attention. Even Sadie's fascinated.
Sadie
I'm scared I might die.