Estimate the difference in energy between 1st and 2nd Bohr orbit for a hydrogen atom. At what minimum atomic number, a transition from n = 2 to n = 1 energy level would result in the emission of X-rays with $$\lambda = 3.0 \times {10^{ - 8}}$$? Which hydrogen atom like species does this atomic number correspond to?

What transition in the hydrogen spectrum would have the same wavelength as the Balmer transition n = 4 to n = 2 of He⁺ spectrum?

According to Bohr's theory, the electronic energy of hydrogen atom in the n^th Bohr's orbit is given by $${E_n} = {{ - 21.6 \times {{10}^{ - 19}}} \over {{n^2}}}J$$. Calculate the longest wavelength of light (in Å) that will be needed to remove an electron from the third Bohr orbit of the He⁺ ion.

Give reasons why the ground state outermost electronic configuration of silicon is: