- 2018: The radius of the first Bohr orbit of the hydrogen atom is 0.53 Å. The radius of the third Bohr orbit of the hydrogen atom will be
A) 1.59 Å B) 4.77 Å C) 9.54 Å D) 3.18 Å
Answer: B
Explanation:
The radius of the nth Bohr orbit of the hydrogen atom is given by
r = n^2 a_0
where
ris the radius of the orbit in angstromsnis the principal quantum numbera_0is the Bohr radius, which is equal to 0.53 Å
In this problem, we are given that the radius of the first Bohr orbit is 0.53 Å. We are asked to find the radius of the third Bohr orbit. Substituting n = 3 into the equation for the radius of the nth Bohr orbit, we get
r = 3^2 a_0 = 9 a_0 = 4.77 Å
