11. Multi-electron atoms

Question 1

How do binding energies and the Bohr radii scale w.r.t the atomic number?

Answer 1

Binding energy as Z^2
Bohr radii as Z^-2
Provided the atom has been ionised so it only has 1 electron

Question 2

What does the concept of indistinguishability state?

Answer 2

That it is not possible to put a label on an electron in an atom and follow it

Question 3

What does the concept of exchange symmetry state?

Answer 3

If you label both electrons in a He atom, you must be able to swap the labels without changing the properties of the system

Question 4

Briefly describe the Pauli exclusion principle

Answer 4

No two electrons in a multi electron atom may have the same quantum state

Question 5

How can an electron be in a different quantum state to another electron?

Answer 5

By having different quantum numbers (n, l, m_l, s)

Question 6

How many electrons can occupy a n, l, m_l state?

Answer 6

2 - spin up and down

Question 7

In a multi-electron atom, how are quantum states filled up?

Answer 7

From the highest binding energy (most -ve) to the lowest