physical chemistry foe biochemistry II

1. (25 pts) Using the Bohr model, calculate the radius for the electron in the n=1 energy level for a hydrogen atom (1 proton and 1 electron) and a helium cation (2 protons, 2 neutrons and 1 electron). Explain why the radii are either the same or different.
2.
(20 pts) Explain the difference between an eigenvalue and an expectation value (<3-5 sentences).

3.
(25 pts) What is the kinetic energy for a proton with the following wavefunction? (Hint: the
‘m-1’ in the wavefunction is the unit of ‘meter’ to the power of -1)

4.
(20 pts) Calculate the expectation value for the ‘F’ operator given the following wavefunction and relationships.

5.
(10 pts) The particle in a 1D box has an infinite potential, V = , at x < 0 and x > L. A modified particle in a 1D box additionally has an infinite potential at exactly x = L / 2. Using
equations, show how this modifies the eigenfunctions and energy levels.

|Ψ(x) = 1
3 cos(3m 1 x)

|ψ = c|φ1 + 2c|φ2
̂
F|φ1 = 1 |φ2
̂
F|φ2 = 0
c* = c
φi | φj = 0 when i j
φi | φj = 1 when i = j