The electron energy is hydrogen atom is given by `E"(n)=(-2.18xx10^(-18)) J`. Calculate the energy required to remove an electron completely from the n=2 orbit. What is the longest wavelength of light in cm that can be used to cause this transition?

Explanation

`E_(2)=-(2.18xx10^(-18))/((2)^(2))J=-5.45xx10^(-19)J`
Energy required to remove an electron completely from the orbit with `n=2, DeltaE=E_(oo)-E_(2)=0-(-5.45xx10^(-19)J)`
`=5.45xx10^(-19)J(becauseE_(oo)=0)`
Again, `lamda=(hc)/(DeltaE)=((6.626xx10^(-34)J*s)xx(3xx10^(8)m*s^(-1)))/(5.45xx10^(-19)J)`
`=3.647xx10^(-7)m=3.647xx10^(-5)m`