In a coagulation experiment , a sol of `As_2S_3` is mixed with distilled water and 0.2m solution of an electrolyte, AB so that total volume is 20 mL. It was found that all solutions containing more than 4.5mL of AB get coagulated within two minutes. What is the flocculation value of AB for `As_2S_3` ?

Explanation

To find the flocculation value of the electrolyte AB for the sol of As₂S₃, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Coagulation**: Coagulation is the process where a colloidal solution is precipitated by adding an excess of electrolyte. In this case, we need to determine how much of the electrolyte AB is required to coagulate the As₂S₃ sol.

2. **Volume of Electrolyte Used**: It is given that more than 4.5 mL of the 0.2 M solution of AB is required to coagulate the As₂S₃ sol. Therefore, we can use this volume to calculate the amount of moles of AB used.

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