Practicing Success

Target Exam

CUET

Subject

Physics

Chapter

Atoms

Question:

An atom of hydrogen has an electron in some excited state having radius of 8.48 × 10-10 m. The electron will lie in orbit of which principle quantum number (n) (given Bohr radius, a0 = 5.3 × 10-11 m)?

Options:

n = 3

n = 4

n = 2

None of the above

Correct Answer:

n = 4

Explanation:

r= n2h2ε0/mπe or n2r1                        (r1 is Bohr radius, a0)

n=  rn/a0

$n^2= \frac{8.48 \times 10^{-10}}{5.3 \times 10^{-11}}= 16$

n  = 4