Identify element x

[chjopl]

From the information below identify element x:
A. The wavelength of the radio waves sent by an FM station brodcasting at 97.1 MHz is 30 million times greater than the wavelength corresponding to the energy difference between a particular excited state of the hydrogen atom and the ground state.
B. Let "M" represent the principal number for the valence shell of element x. If an electron in the hydrogen atom falls from the shell "M" to the inner shell corresponding to the excited state mentioned above in part A, the wavelength of light emiited is the same as the wavelength of an electron moving at the speed of 570m/s
C. The number of unpaired electrons for element X in the ground state is the same as the maximum number of electons in an atom that can have the quantum number designations: n=2, ml=-1, m=-1/2
D. Let A equal the charge of the stable ion that would form when the undiscovered element 120 forms ionic compounds. This value of A also represents the angular (or azimuthal) quantum number for the subshell containing the unpaired electron(s) for element X.

Please help me with this...all this did was confuse me

[ShawnD]

From the information below identify element x:
A. The wavelength of the radio waves sent by an FM station brodcasting at 97.1 MHz is 30 million times greater than the wavelength corresponding to the energy difference between a particular excited state of the hydrogen atom and the ground state.
For this part, I get that the wavelength is 1.0287 E -7 m for the energy difference between the excited state of hydrogen and the ground state. Convert this number into energy using planck's constant.

B. Let "M" represent the principal number for the valence shell of element x. If an electron in the hydrogen atom falls from the shell "M" to the inner shell corresponding to the excited state mentioned above in part A, the wavelength of light emiited is the same as the wavelength of an electron moving at the speed of 570m/s
One part is bolded because it's important.
Here you are told to add the energy of an electron at 570m/s to the energy of the excited state found in part A. Energy from part A + energy from part B = energy at level M. If you have a table of hydrogen energy levels, you can easily find the value for M.

C. The number of unpaired electrons for element X in the ground state is the same as the maximum number of electons in an atom that can have the quantum number designations: n=2, ml=-1, m=-1/2
Can't basically any atom with a 2px electron have these numbers? Maybe it just refers to Boron which has 5 electrons. 5 unpaired electrons would mean the atom is in the same column as Mn. The atom is either Mn, Tc, Re, or Bh.

D. Let A equal the chare of the stable ion that would form when the undiscovered element 120 forms ionic compounds. This value of A also represents the angular (or azimuthal) quantum number for the subshell containing the unpaired electron(s) for element X.
I have no idea what this means.

[chjopl]

I am still having trouble figuring out B and D....anyone able to help??