What is the change in the orbit radius when the electron in the hydrogen atom (Bohr model) undergoes the first Paschen transition ?

Options

A. `4.23 xx 10^-10 m`
B. `0.35 xx 10^-10 m`
C. `3.7 xx 10^-10 m`
D. `1.587 xx 10^-10 m`

Answer

C

Explanation

( c) `r_3 = 0.529 xx (n^2)/(Z) Å`
`r_4 = 0.529 xx (n^2)/(Z) Å`
`r_4 - r_3 = 0.529 xx (16)/(1) - 0.529 xx (9)/(1) Å`
=`0.529 xx 10^-10 [16 - 9] m`
=`7 xx 0.529 xx 10^-10`
=`3.7 xx 10^-10 m`.