1. Consider the He atom. The Hamiltonian is
What is the perturbation Hamiltonian?
(A)
(B)
(C)
(D)

2. Consider the He atom. The Hamiltonian is
What is the perturbation Hamiltonian?
(A)
(B)
(C)
(D)

3. If we neglect the electron-electron interaction, the total wave
function of the He atom in the ground state is ...
(A) ... the sum of two 1s electron wave functions
(B) ... the difference of two 1s electron wave functions
(C) ... the product of two 1s electron wave functions

4. If we neglect the electron-electron interaction, the total wave
function of the He atom in the ground state is ...
(A) ... the sum of two 1s electron wave functions
won’t be normalized any more!
(B) ... the difference of two 1s electron wave functions
(C) ... the product of two 1s electron wave functions
||2 correctly describes probability density as |(1)|2 |(2)|2

5. What is electron spin?
(A) It’s the same as the orbital angular momentum of the electron.
(B) It’s a form of angular momentum, but it is described by half-integer
quantum numbers.
(C) It’s just another form of angular momentum, adding 1ħ to the
orbital angular momentum.
(D) It’s another form of angular momentum with quantum numbers going
from s = 0 to s = ℓ.
(E) It’s another form of angular momentum with possible quantum
numbers s = 1 and s = 3 (singlet and triplet states).

6. What is electron spin?
(A) It’s the same as the orbital angular momentum of the electron.
(B) It’s a form of angular momentum, but it is described by half -integer quantum numbers.
(C) It’s just another form of angular momentum, adding 1ħ to the
orbital angular momentum.
(D) It’s another form of angular momentum with quantum numbers going
from s = 0 to s = ℓ.
(E) It’s another form of angular momentum with possible quantum
numbers s = 1 and s = 3 (singlet and triplet states).