Calculate the energy in joules and the wavelength in nanometers of the spectral line produced in the hydrogen spectrum when an electron falls from the tenth Bohr orbit to the fourth

Question

Calculate the energy in joules and the wavelength in nanometers of the spectral line produced in the hydrogen spectrum when an electron falls from the tenth Bohr orbit to the fourth. In which region of the electromagnetic spectrum (UV, visible, or infrared) is the line? Report all numerical answers to three significant figures.

Answer 1

Just to add the @Jacques D.'s answer.

∆E = R_H (1/n_f² - 1/n_i²)

R_H = -2.179x10^-18 J

n_f = final energy level = 4

n_i = initial energy level = 10

∆E = change in energy in joules (J)

∆E = -2.179x10^-18 J (1/10² - 1/4²) = -2.179x10^-18 J (0.01 - 0.25) = -2.179x10^-18 J (-0.24)

∆E = 5.2x10^-19 J

Answer 2

!st,, you need the Rydberg constant in Joules. It's also equal to E₁ in Bohr's model

E_nm = R_y(1/m² - 1/n²)