1. What is ionization energy? How does it change as you go across a row in the periodic table? Be sure to use the coulombic attraction between electrons and the nucleus in your explanation.
2. How does ionization energy change as you go down a group in the periodic table? Be sure to use the coulombic attraction between electrons and the nucleus in your explanation.
3. Based on the figure above, what is the relationship between the ionization energy of Element 2 and the size of the band gap? Explain why this might be. Be sure to use the coulombic attraction between electrons and the nucleus in your explanation.
4. Someone proposes to make a new LED using gallium and antimony. What would you predict about its band gap relative to the LEDs in the table?
5.You can also make LEDs with three elements in them. Which of the mixtures do you think would make a yellow LED? Be sure to explain your reasoning.
Gallium with Nitrogen/Phosphorous (50:50 mix)
Gallium with Phosphorous/Arsenic (50:50 mix)
