How Does Electron Energy Affect Atomic and Nuclear Dimensions?

[liaminho]

I need help with these two questions:

1. Electron diffraction can be used to investigate both the arrangement of atoms and the dimensions of nuclei. Explain how changing the energy of the electrons can be used to achieve this.

And...

2. Uranium has atomic number 92. Two of its common isotopes have nucleon numbers 235 and 238. How many neutrons are there in a nucleus of each of these isotopes?

 

[liaminho]

Actually, ignore question 2. I can do that one :)

 

[Doc Al]

Look up "deBroglie wavelength". Examples of Electron Waves