Question

If the atom ${}_{100}F{m}^{257}$ follows the Bohr model and the radius of ${}_{100}F{m}^{257}$ is n times the Bohr radius, then find $n$.

• A. $100$
• B. $200$
• C. $4$
• D. $1/4$

Answer 1

The correct option is D $1/4$

For an atom following Bohr's model, the radius is given by $r_m=\frac{r_0{m}^2}{Z}$

where $r_0=$Bohr's radius and $m=$ orbit number.
For $Fm,m=5$ (Fifth orbit in which the outermost electron is present)
$\therefore r_m=\frac{r_0{5}^2}{100}=n{r}_0$ (given) $\Rightarrow n=\frac{1}{4}$