Chemistry - Atomic Structure Question with Solution | TestHub

The centripetal force $F_c$ is given by $F_c=\frac{m{v}^2}{r}$.

Given:

Mass of electron $m=9.1\times 10^{-31}$ kg

Radius $r=0.53$ Å $=0.53\times 10^{-10}$ m

Speed $v=2.2\times 10^6$ m/s

$F_c=\frac{(9.1\times 10^{-31}kg)\times (2.2\times 10^{6}m/s{)}^2}{0.53\times 10^{-10}m}$

$F_c=\frac{9.1\times 10^{-31}\times 4.84\times 10^{12}}{0.53\times 10^{-10}}$

$F_c=\frac{44.044\times 10^{-19}}{0.53\times 10^{-10}}$

$F_c=83.10\times 10^{-9}$ N

To express in $10^{-8}$ N:

$F_c=8.31\times 10^{-8}$ N

Approximated to the nearest integer, the value is 8.