Question

The wavelength in Å of the photon that is emitted when an electron in Bohr orbit with n = 2 returns to orbit with n = 1 in H atom is ______ Å. The ionisation potential of the ground state of the H-atom is 2.17 × 10⁻¹¹ erg.

विकल्प

• 850

• 1050

• 1216

• 1350

Answer 1

The wavelength in Å of the photon that is emitted when an electron in Bohr orbit with n = 2 returns to orbit with n = 1 in H atom is 1216 Å. The ionisation potential of the ground state of the H-atom is 2.17 × 10⁻¹¹ erg.

Explanation:

Here, n₁ = 1, n₂ = 2

`1/λ = "R"_"H""Z"^2 [1/"n"_1^2 - 1/"n"_2^2]`

= `"R"_"H" [1 - 1/4] ...[∵ 1/"R"_"H" = 912 Å]`

`1/λ = "R"_"H" xx 3/4`

λ = `4/(3"R"_"H")`

λ = `4/(3 xx 912)`

λ = 1216 Å