Question

calculate the wavelength of spectral lines of balmer series when y=3 (n=3)

Answer 1

we know that for balmer series of lines n₁ = 2 and given in the question n₂ = 3

wave number for balmer series = 109677(1/n₁² - 1/n₂²) cm⁻¹

substituting n₁ = 2 and n₂ = 3 in the wave number equation

wave number for balmer series = 109677(1/4 - 1/9)

wave number for balmer series = 109677(5/36) = 15232.91 cm⁻¹ = 152.3291 m⁻¹

we know that wave number is the reciprocal of wavelength

wave length for balmer series = 1/152.3291 = 0.006564 m = 6.564 mm.