The radii of the Bohr orbits in atomic hydrogen are given by .If the radius of the first Bohr orbit n = 1) is 0.053 nm, the radius of the third Bohr orbit n = 3) is
A) 0.16 nm.
B) 0.018 nm.
C) 0.48 nm.
D) 0.35 nm.
E) 1.3 nm.

Question

The radii of the Bohr orbits in atomic hydrogen are given by  .If the radius of the first Bohr orbit n = 1) is 0.053 nm, the radius of the third Bohr orbit n = 3) is
A) 0.16 nm. 
B) 0.018 nm. 
C) 0.48 nm. 
D) 0.35 nm. 
E) 1.3 nm.

Quizplus · Accepted Answer

The radius of the nth Bohr orbit is given by $r_n=n^2\cdot r_1$, where $r_1$ is the radius of the first Bohr orbit. Thus, $r_3=3^2\cdot 0.053\; \mathrm{nm}=0.48\; \mathrm{nm}$. Therefore, the correct choice is (C).

The Radii of the Bohr Orbits in Atomic Hydrogen Are