Consider two radiations of wavelengths $1. \lambda_1 = 2000 \mathring{A}$ and $2. \lambda_2 = 6000 \mathring{A}$. The ratio of the energies of these two radiations $\left(\frac{E_1}{E_2}\right)$ is . . . . . . (Nearest integer).

Electromagnetic radiation of wavelength $663 \ nm$ is just sufficient to ionise the atom of metal $A.$ The ionization energy of metal $A$ in $kJ \ mol^{-1}$ is ...... .
(Rounded-off to the nearest integer) $\left[ h = 6.63 \times 10^{-34} \ Js, c = 3.00 \times 10^{8} \ ms^{-1}, N_{A} = 6.02 \times 10^{23} \ mol^{-1} \right]$

Which of the following is not a property of photons?

Calculate the wavenumber $\bar{v}$ in $cm^{-1}$ for yellow radiation having a wavelength of $5800 \ \mathring{A}$.

Which one of the following frequencies of radiation (in $Hz$) has a wavelength of $600 \ nm$?

Calculate the energy of one mole of photons of radiation whose frequency is $5 \times 10^{14} \ Hz$.