What is the wavelength of light for the least energetic photon emitted in the Lyman series of the hydrogen spectrum, (take hc = 1240 eV nm)

Question

What is the wavelength of light for the least energetic photon emitted in the Lyman series of the hydrogen spectrum, (take hc = 1240 eV nm) (A) 82 nm (B) 102 nm (C) 122 nm (D) 150 nm

Tardigrade Admin · Accepted Answer

Given, hC=1240 eV For least energetic photon E=E2-E1=10.2 eV We know that, E=(h c/λ) ; λ=(h c/E) ; λ=(1240/10.2) λ=121.56 ≈ 122 nm

Q. What is the wavelength of light for the least energetic photon emitted in the Lyman series of the hydrogen spectrum, (take $h c = 1240 e V nm$ )

82 nm

102 nm

122 nm

150 nm

Given, $h_{C} = 1240 e V$
For least energetic photon $E = E_{2} - E_{1} = 10.2 e V$
We know that, $E = \frac{h c}{λ}; λ = \frac{h c}{E}; λ = \frac{1240}{10.2}$
$λ = 121.56 \approx 122 nm$

Q. What is the wavelength of light for the least energetic photon emitted in the Lyman series of the hydrogen spectrum, (take hc=1240eVnm)