Hydrogen atoms are excited by a laser to the =4 state and then allowed to emit. What is the maximum number of distinct emission spectral lines (lines of different wavelengths) that can be observed from this system? Calculate the wavelength of the 4⟶3 transition.

1875 nm

Explanation:

Given the Rydberg formula for hydrogen: 1/λ = R(1/n₁² - 1/n₂²)

where R ≈ 1.097* 10^7 /m

Hence;

1/λ = 1.097* 107/m * (1/3² - 1/4²) = 5.3 * 10^5/m

λ = 1.875 * 10-6 m = 1875 nm

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