in a hypothetical element, two energy levels are separated by an energy of 282 kj mol. what wavelength of light (in nm) is involved for an electron to change between these two levels?

425 nm

Explanation:

If 1 mol = 6.02 * 10^23

The energy (E)= 282 * 10^3/6.02 * 10^23 = 4.684 * 10^-19 J

Now;

E = hc/λ

h = Plank's constant = 6.63 * 10^-34 Js

c = speed of light= 3 * 10^8 m/s

λ = Wavelength of light = ?

4.684 * 10^-19 = 6.63 * 10^-34 * 3 * 10^8/λ

λ  = 6.63 * 10^-34 * 3 * 10^8/4.684 * 10^-19

λ  = 4.25 * 10^-7 m

λ  = 425 * 10^-9 m

λ  = 425 nm

h let me think