Answer:
2.2 x 10⁻³⁴ J
or
2.2 x 10⁻¹⁸ J
Step-by-step explanation:
You can calculate the energy using the photon energy equation:
E = hc / λ
In this equation,
-----> E = energy (J)
-----> h = Planck's Constant (6.626 x 10⁻³⁴ J*s)
-----> c = speed of light (3.0 x 10⁸ m/s)
-----> λ = wavelength (m)
You can plug the given wavelength, along with the other constants, into the equation and simplify to find the energy.
E = hc / λ
E = (6.626 x 10⁻³⁴ J*s)(3.0 x 10⁸ m/s) / (9 x 10⁸ m)
E = 2.2 x 10⁻³⁴ J
I suspect that you may have forgotten the negative sign in front of the 8 (9 x 10⁻⁸). This would change your answer to 2.2 x 10⁻¹⁸ J.