NEETChemistrySurface Chemistry
Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R . Assertion A : Finest gold is red in colour, as the size of the particles increases, it appears purple then blue and finally gold. Assertion R : The colour of the colloidal solution depends on the wavelength of light scattered by the dispersed particles. In the light of the above statements, choose the most appropria
Options
- ABoth A and R are true and R is the correct explanation of A
- BBoth A and R are true but R is NOT the correct explanation of A
- CA is true but R is false
- DA is false but R is true
Correct answer
A. Both A and R are true and R is the correct explanation of A
Step-by-step solution
The colour of colloidal solution depends on the wavelength of light scattered by the dispersed particles. The wavelength of light further depends on the size and nature of the particles. The colour of colloidal solution also changes with the manner in which the observer receives the light. For example, a mixture of milk and water appears blue when viewed by the reflected light and red when viewed by the transmitted light. Finest gold sol is red in colour; as the size of particles increases, it appears purple, then