Question

For the coagulation of `500mL` of arsenious sulphide sol, `2mL` of `1MNaCl` is required. What is the flocculation value of `NaCl` ?

Answer 1

Correct Answer - 4
2mL of 1M NaCl contains `NaCl=(2)/(1000)=2` mmol
Thus 500 mL of `As_(2)S_(3)` sol require NaCl for complete coagulation=2mmol
Hence 1L, i.e., 1000 mL of the sol reqruie NaCl for complete coagulation=4mmol
Therefore, flocclation value of NaCl=4