Find the frequency and wavelength of light required for the ionization of the solution. (Ionization energy of the solution $= 8.2 \times 10^{-19} \ J$)

The ionization energy $E$ is given by $E = h\nu = \frac{hc}{\lambda}$.
Given $E = 8.2 \times 10^{-19} \ J$,$h = 6.626 \times 10^{-34} \ J \cdot s$,and $c = 3 \times 10^8 \ m/s$.
Frequency $\nu = \frac{E}{h} = \frac{8.2 \times 10^{-19}}{6.626 \times 10^{-34}} \approx 1.238 \times 10^{15} \ Hz$.
Wavelength $\lambda = \frac{hc}{E} = \frac{(6.626 \times 10^{-34}) \times (3 \times 10^8)}{8.2 \times 10^{-19}} \approx 2.42 \times 10^{-7} \ m = 242 \ nm$.