Explain these lines 
Colloidal solutions viewed in sane way also appear reasonably clear or translucent by the transmitted light but tgey show a mild to strong opalescence ,when viewed at right angles to the passage of light i.e path is illumineated by bluish light

Asked by vinodjoshi112233 | 25th Jun, 2017, 05:03: PM

Expert Answer:

Colloidal solutions viewed in same way also appear reasonably clear or translucent by the transmitted light but they show a mild to strong opalescence, when viewed at right angles to the passage of light i.e path is illumineated by bluish light.
This is because, the transmitted light as word suggest is the light passed through the solution straight from source to our eyes as it has not got disturbed or distracted by any colloidal particle. Hence this path is  clear where no collodal particles come inbetwwen the source and our eyes.
While the scattered light path i.e. bluish light or viwed in 90 degree, is the path of light which has got distracted due to presence of colloidal particles. Hence, this path is unclear.
 

Answered by Prachi Sawant | 28th Jun, 2017, 11:09: AM