20 mL of 0.5 M NaCl is required to coagulate 200 mL of As2S3 solution in 2 hours. The coagulating value of NaCl is____
Show Hint
Coagulating value is inversely proportional to the coagulating power of an electrolyte
Correct Answer: 50
Solution and Explanation
Coagulating Value Calculation
Definition: The coagulating value is defined as the amount of electrolyte (in millimoles) required to coagulate 1L of colloidal solution in 2 hours.
Calculation
- Moles of NaCl used:
Moles = M × V = 0.5 × 20 mL = 10 mmol
- Coagulating Value:
Coagulating Value = 10 200 × 1000 = 50
Final Answer
The coagulating value is 50.
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