Question

Calculate the wavelenght of light emiited when the electron in a hydrogen atom undergoes transition from an energy level n=4 to an energy level n=2?

Answer 1

Here,
n₁ = 2, n₂ = 4
We know,

1/λ = R (1/n₁² - 1/n₂²)

Or 1/λ = 1.097 × 10⁻⁷ (1/4 - 1/16)

Or 1/λ = 1.097 × 10⁻⁷ (3/16)

Or 1/λ = 0.205 × 10⁻⁷

Or λ = 1/(0.205 × 10⁻⁷)

Or λ = 4.87 × 10⁷ m

Hence the wavelength of your required circumstance is 4.87 × 10⁷