Radius of the third Bohr orbit of the electron of the hydrogen atom is (Given `h=6.625xx10^(-34)J-s,e=1.6xx10^(-19)C,epsi_(0)=8.85xx10^(-12)Fm^(-1)`)

Options

A. 2.48 Å
B. 3.68 Å
C. 2.68 Å
D. 4.77 Å

Answer

D

Explanation

Here, `h=6.625xx10^(-34)Js`
`e=1.6xx10^(-19)C`
`m=9.1xx10^(-31)kg`
`c=3xx10^(8)ms^(-1)`
`epsi_(0)=8.85xx10^(-12)Fm^(-1) and n=3`.
Radius of the nth Bohr orbit of the hydrogen atom is given by
`r_(n)=4piepsi_(0)*(n^(2)h^(2))/(4pi^(2)me^(2))`
`r_(3)=4pixx8.85xx10^(-12)xx((3)^(2)xx(6.625xx10^(-34))^(2))/(4pi^(2)xx9.1xx10^(-31)xx(1.6xx10^(-19))^(2))`
`=4.779xx10^(-19)m=4.779`Å