Answer:
626.7nm
Explanation:
The energy of a photon is defined as:
E = hc / λ
Where E is the energy of the photon, h is Planck constant (6.626x10⁻³⁴Js), c is speed of light (3x10⁸m/s) and λ is the wavelength of light
The energy of 1 photon is:
(191000 J / mol) ₓ (1 mole / 6.022x10²³) = 3.1717x10⁻¹⁹ J
Replacing:
3.1717x10⁻¹⁹ J = 6.626x10⁻³⁴Jsₓ3x10⁸m/s / λ
λ = 6.267x10⁻⁷m
as 1nm = 1x10⁻⁹m:
6.267x10⁻⁷m ₓ (1nm / 1x10⁻⁹m) =
626.7nm
