For atoms of light and heavy hydrogen `(H and D)` fine the difference,
(a) between the binding energies of their electrons in the ground state.
(b) between the wavelength of first lines of the Lyman series.

Answer

`E_(D)-E_(H)=3.7meV, lambda_(H)-lambda_(D)=33"pm"`

Explanation

(a) `(E_(n))= -13.6xx(1)/(1+(m_(e ))/(m_(H))).(1)/(n_(2))eV`
`(E_(n))_(D)= -13.6xx(1)/(1+(m_(e ))/(m_(D))).(1)/(n_(2))eV`
`DeltaE= 13.6xx((1)/(1+(m_(e ))/(m_(D)))-(1)/(1+(m_(e ))/(m_(H))))eV`
`~~13.6[(2-(m_(e ))/(m_(D)))-(1-(m_(e ))/(m_(H)))]eV`
(b) `(1)/(lambda_(H))=(1)/(1+(m_(e ))/(m_(H)))Roo(1-(1)/(4))`
`(1)/(lambda_(D))=(1)/((m_(e ))/(m_(D))).Roo(1-(1)/(4))`
`lambda_(H)-lambda_(D)=33 "pm"`