Summary

• Photoelectric effect & photons
• Bohr model of the atom
• de Broglie waves

• The quantum mechanical atom
  • four quantum numbers
  • H orbitals
  • Pauli exclusion principle
  • the periodic table
  • summary
  
  
  
  
  
• The nucleus
  • protons & neutrons
  • stable & unstable isotopes
  
  
  
• Radioactive decay
  • alpha decay
  • beta minus decay
  • gamma decay
    Example #1
    
  • exponential decay curves applet 1
    applet 2
  • half-life & radioactive clocks
    Example #2
    
    Example #3
    
  
  

 
Uranium-236 () undergoes alpha decay.
What is its daughter isotope?

A.        B.        C.        D.
Answer













 
If you start with 2 kg of a radioactive substance, how much will you have after 4 half-lives?
A. 125 g           B. 500 g           C. 2 kg           D. 8 kg
Answer













 
If the ratio of ¹⁴C to ¹²C in a piece of bone is only 1/8 of the atmospheric ratio, how old is the bone? The half-life of ¹⁴C is 5700 years.
A. 713 y           B. 1900 y           C. 17,100 y           D. 45,600 y
Answer













 



B.


















 



A. 125 g


















 



C. 17,100 years