Calculate the wavelength of light that must be absorbed by hydrogen atom in its ground state to reach the excited ste of E=+2.914*10^(-18)

Answer 1

E = hc/λ where h = 6.626 E -34 Js

+2.914*10^(-18) J = [6.626*10^(-34) Js (3*10^8) m/s] / λ

so do some mathematical manipulation and isolate λ to get:

λ = [6.626*10^(-34) Js (3*10^8) m/s] / +2.914*10^(-18) J

& you can use a calculator to get the final answer :)