Question

Estimate the difference in energy between 1st and 2nd Bohr's 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  λ = 3.0 x 10^-8 m ? Which hydrogen atom-like species does this atomic number correspond to ?

Answer 1

 

For the species emitting X-rays with λ = 3.0 x 10^-8 m or 3.0 x 10^-6 cm

The atomic number'of such species is 2. Hence, it is He⁺ because Bohr's theory is applicable for mono-electronic species.