Chemistry - Atomic Structure Question with Solution | TestHub

A sealed gas chamber filled with ${\mathrm{H}}_2$ gas was irradiated with light of wavelength $\lambda \mathrm{nm}$, so that all of the ${\mathrm{H}}_2$ gas dissociates and temperature increase of $7680^{\circ }\mathrm{C}$ was observed. Assume no energy loss.

Given:

(i) All ${\mathrm{H}}_2$ gas converts into H-atoms

(ii) $H-H$ bond energy $=480\mathrm{kJ}/\mathrm{mol}$.

(iii) $R=\frac{25}{3}J/mol-K,N_A=6\times 10^{23}$ (assume ideal behaviour)

(iv) 1 $\frac{eV}{atom}$= 96 $kJmo{l}^{-1}$

Calculate the maximum possible value of $\lambda$ (in nm ).