In an experiment, addition of `4.0mL` of `0.005MBaCl_(2)` to `16.0mL` of arsenious sulphide sol just cause the complete coagulation in `2h` . The flocculating value of the effective ion is:

Options

A. `Cl^(Θ),1.0`
B. `Cl^(Θ),2.0`
C. `Ba^(2+),1.0`
D. `Ba^(2+),0.5`

Explanation

`As_(2)S_(3)` sol is negatively charged owing to preferntial adsorption of `S^(2-)` ions. Cation would be the effective ions in coagulation.
Flocculating value = minimum milli of the effective
Ion per litre of sol the effective ion per litre of sol `=(4xx0.005xx10^(3))/(4+16)=1.0`