Chemistry

Problem

Which of the following expressions correctly represents the dependence of the radius

r_n

of the

n^{\text{th}}

Bohr orbit of a hydrogen-like ion on the principal quantum number

n

and atomic number

Z

? a)

r_n \propto \dfrac{n}{Z}

r_n \propto \dfrac{Z}{n^2}

r_n \propto \dfrac{n^2}{Z}

r_n \propto n^{2}Z