What type(s) of atomic orbitals are pictured below?

Consider the following sketch of the interaction energy for two atoms as a function of distance between the atoms.

Label e) refers to the point where the interaction energy is lowest and shows how the stable bond length is calculated.  At this point ____________

What wavelength corresponds to the boundary between visible and IR radiation.

Consider the energy level diagram sketch below.

Which of the transitions, a) - e), represents a hydrogen atom in an excited state emitting light and ending up in its ground state?

An atom is in its ground state if: 

Which wavelength corresponds to the boundary between UV and visible radiation?

The partial pressure of O₂ in the atmosphere at sea level is 21.3 kPa. What is the partial pressure of O₂ on the top of a mountain, where the atmospheric pressure is 84.9 kPa?

[Atmospheric pressure at sea level is 101.3 kPa.]

How many s, p and d orbitals exist when n = 3, respectively?

How many atomic orbitals have the principal quantum number n = 2?

What is the maximum number of electrons that can be accommodated, in total, for all of the 3d orbitals?