Photogray lenses incorporate small amounts of silver chloride in the glass of the lens.?

Question

Photogray lenses incorporate small amounts of silver chloride in the glass of the lens. When light hits the AgCl particles, the following reaction occurs.

AgCl Ag + Cl

The silver metal formed causes the lenses to darken. The enthalpy change for this reaction is 3.10 102 kJ/mol. Assuming all this energy must be supplied by light, what is the maximum wavelength of light that can cause this reaction?

_____ nm

Answer 1

386 nm is the answer