The ionisation energy of hydrogen atom in the ground state is x KJ. The energy required for an electron to jump from 2^nd orbit to 3^rd orbit is

A. 5x/36

B. 5x

C. 7.2 x

D. x/6

Answer: Option A

Solution(By Examveda Team)

The ionisation energy for the hydrogen atom can be written as:
Ionisation energy = energy in first orbit - energy in infinite orbit
Ionisation energy = ​ E = -E₀ / n² , where E₀  = 13.6 eV (1 eV = 1.602×10^-19  Joules) and n = 1,2,3… and so on.
The difference in energy = Einfinity - E1
so the ionisation energy from the ground state = x KJ = 0-( -E₀ /1² ) = E₀
The energy required to jump the elctron from second to the third stage is: