Rutherford created a theoretical picture of the atom based on :

The radius of the $2^{nd}$ orbit of $B^{4+}$ ion is:

Emission transitions in the Paschen series end at orbit $n=3$ and start from orbit $n$ and can be represented as $\nu = 3.29 \times 10^{15} \, Hz \left(\frac{1}{3^2} - \frac{1}{n^2}\right)$. Calculate the value of $n$ if the transition is observed at $1285 \, nm$. Find the region of the spectrum.

In a hydrogen atom, the minimum energy required to excite an electron from the $2^{nd}$ orbit to the $3^{rd}$ orbit is: (in $eV$)

Which of the following transitions has the minimum wavelength?

Find the frequency and wavelength of light required for the ionization of the solution. (Ionization energy of the solution $= 8.2 \times 10^{-19} \ J$)