Lecture on Nuclear Chemistry and Energy

Introduction

• The search for stability is central to chemistry and life.
• Last week covered: Radioactive decay and atomic nuclei stability.
• Nuclear stability involves keeping the nucleus intact.
• Binding energy: Energy holding protons and neutrons in the nucleus.
• Mass-energy equivalence: Introduced by Einstein’s famous equation E = mc².

Mass-Energy Equivalence (E = mc²)

• Formula relates mass and energy through a proportional constant (speed of light squared).
• Mass defect: Difference in mass between a nucleus and its nucleons.
• Example: Oxygen nucleus mass defect and binding energy calculation.
  • Binding energy for oxygen nucleus: 2.04 x 10^-11 joules.
  • Energy for a mole of oxygen: 1.23 x 10^13 joules (equivalent to burning 420 metric tons of coal).

Nuclear Reactions

• Fission: Large nucleus splits into lighter ones.
• Fusion: Light nuclei combine to form heavier ones.
• Both reactions aim to increase stability.

Fission Details

• More control over fission than fusion.
• Commonly used fuel: Uranium-235.
• Initiated by neutron bombardment.
• Produces products like krypton-92, barium-141, free neutrons, and energy.
• Energy used in nuclear power plants to generate electricity.
• Chain reactions can lead to meltdowns if uncontrolled.
• Controlled using water and control rods.

Fusion Details

• Fusion reactions release more energy than fission.
• Example: Sun's hydrogen fusion process.
• Fusion reactions require high temperatures and pressures.
• Difficult to control for practical energy use.

Applications and Challenges

• Fission: Used in power plants and weapons.
• Fusion: Potential for tremendous energy but hard to control.
• Challenges include controlling fusion, storing radioactive waste, and safe application.

Conclusion

• Emphasized the potential for new ideas in nuclear chemistry.
• Understanding basics opens doors to future innovations.
• Episode credits: Written by Edi González, edited by Blake de Pastino. Chemistry consultant, Dr. Heiko Langner.