Which of the following statements is/are correct with respect to surface phenomenon ?

Options

A. Potassium ferrocyanide can cause greater coagulation in a basic dye as compared to `Na_(2)HPO_(3)`.
B. A starch aqua-sol can act as a protective colloid for `Fe(OH)_(3)` sol.
C. The slope of the Freundlich Isotherm (log `(x)/(m)` vs log p) keeps on changing for a long range of pressure and is constant over a limited range of pressure.
D. On mixing `AgNO_(3)` with large amount of KI and subjecting the colloidal state to electrophoresis, coagulation is obtained at cathode.

Answer

A, B, C

Explanation

(A) `K_(4)[Fe(CN)_(6)]rarr4K^(+)[Fe(CN0_(6)]^(-4)`
`Na_(2)HPO_(3)rarr2Na^(+)+HPO_(3)^(2-)`
higher negative charge over`[Fe(CN)_(6)]^(4-)` so it can cause more coagulation in a basic dye.
(B) Starch aqua-sol is a lyophilic sol so it can be used as protective colloid.
(C) Freundlich adsorption isotherm fails at high pressure