Question

When white light is passed through a colloidal solution containing fine suspended particles of gold, then the scattering light seen in a direction different from that of incident light is:

• A. yellow coloured
• B. blue coloured
• C. green coloured
• D. red coloured

Answer 1

The correct option is B blue coloured

When light is passed through colloidal gold solution it absorbs visible light spectrum and scatters energy of maximum intensity when viewed in a direction other than incident light. More intensity implies more energy which in turn means lower wavelength because $E=\frac{hc}{\lambda }$ .

From given option Blue colour has the least wavelength and is the answer.