(i) The energy associated with the first orbit in the hydrogen atom is -2.18xx10^(-18)" J atom"^(-1). What is the energy associated with the fifth orbit ? (ii) Calculate the radius of Bohr's fifth orbit for hydrogen atom.

(i) The energy associated with the first orbit in the hydrogen atom is

1.	(i) The energy associated with the first orbit in the hydrogen atom is -2.18xx10^(-18)" J atom"^(-1). What is the energy associated with the fifth orbit ? (ii) Calculate the radius of Bohr's fifth orbit for hydrogen atom.
Answer» Solution :(i) `E_(N)=- (2.18xx10^(-18))/n^(2) J :. E_(5)= - (2.18xx10^(-18))/5^(2) =-8.72xx10^(-20) J` (ii) For H-atom, `r_(n)=0.529xxn^(2) Å :. r_(5) =0.529xx5^(2)=13.225 Å=1.3225 NM`