Coagulation value is

Options

A. Minimum concentration of electrolyte required
to cause coagulation
B. Expressed in millimoles per litre
C. Expressed in milligram
D. Also known as flocculation value

Answer

**Step-by-Step Solution:**

1. **Understanding Coagulation:**
- Coagulation refers to the process where colloidal particles aggregate together, leading to the formation of larger particles or precipitates. This occurs when the charge on the colloidal particles is neutralized, allowing them to come closer and settle.

2. **Definition of Coagulation Value:**
- The coagulation value is defined as the minimum concentration of an electrolyte required to cause coagulation of a colloidal solution. This concentration is crucial because it determines how effectively the colloidal particles can be aggregated.

3. **Units of Coagulation Value:**
- The coagulation value is typically expressed in terms of concentration, which can be in moles per liter (mol/L) or millimoles per liter (mmol/L). It is important to note that it is not expressed in milligrams.

4. **Relation to Flocculation:**
- The coagulation value is also referred to as the flocculation value. This term emphasizes the process of flocculation, where particles clump together to form larger aggregates.

5. **Conclusion:**
- Therefore, the coagulation value is the minimum concentration of electrolyte required to cause coagulation, expressed in moles per liter or millimoles per liter, and is also known as the flocculation value.

**Final Answer:**
The coagulation value is the minimum concentration of electrolyte required to cause coagulation, expressed in moles per liter or millimoles per liter, and is also known as the flocculation value.

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