A hydrogen atom initially in the ground level absorbs a photon, Which excites it to n=4 level. Determine the wavelength and frequency of photon.

Answer

`970.6Å`

Explanation

Energy of photon `=E_(4)-E_(1)`
`=-13.6/(4^(2))-(-13.6/(1^(2)))eV`
`E=0.85+13.6=12.75eV`
`E=12.75xx1.6xx10^(-19)J`
`E=(hc)/lambda=12.25xx1.6xx10^(-19)`
`lambda=(hc)/(12.75xx1.6xx10^(-19))`
`lambda=(6.6xx10^(-34)xx3xx10^(8))/(12.75xx1.6xx10^(-19))m`
`lambda=970.6xx10^(-10)M=970.6Å`