Lecture Notes on Cesium Experiment Underwater

Introduction

• Reference to previous videos: sodium and potassium reactions underwater.
• Neil's special device for breaking glass tubes underwater.
• Purpose: To observe the reaction of breaking a 5 gram cesium sample underwater.

Cesium Sample Characteristics

• Commercial sample of cesium, sealed under vacuum (no gas).
• Physical property: Cesium is denser than water, so it cannot float spontaneously.
• Atom comparison: 5 grams of cesium contains the same number of atoms as previous potassium and sodium experiments.

Experimental Conditions

• Filmed outdoors at a different time of day, affecting sunlight angle.
• Observations of surface ripples due to vibrations when the screw was turned.

Reaction Observations

• As the test tube breaks, hydrogen bubbles are released.
• Notable observation: A piece of the test tube shot across the screen but retained cesium.
• Water rushes into the broken test tube, triggering a significant reaction.

Reaction Outcomes

• Explosion characterized by:
  • Bulging of the plastic vessel's sides.
  • Surface water exhibiting large waves akin to a storm or disaster movie.
  • Comparison: Potassium produced minor ripples while cesium caused massive waves.
• Demonstration of cesium's higher reactivity compared to potassium.

Energy Release

• Crude energy meter visualized by observing wave intensity.
• Contrast between potassium (slight waves) and cesium (hurricane-like waves) reactions.

Conclusion

• The cesium experiment showcased cesium's reactivity as significantly higher than potassium.
• Note: No rubidium experiment conducted due to lack of available sample.