Frequency of photon = is 6.85 X 10¹⁴ sec⁻¹
Energy of photon , E = hv
where h is Planck's constant, v is the frequency of photon
E = 6.63 × 10⁻³⁴ J.s x 6.85 X 10¹⁴ s⁻¹
E = 4.54 x 10⁻¹⁹ J
Therefore, the energy of a photon of green light is 4.54 x 10⁻¹⁹ J.
The answer is (4) 4. Germanium is a main group element in group 4A. Therefore, like carbon, it has 4 valence electrons in the ground state.
