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Questions
Write Hardy-Sulze rules.
Write a note on Hardy–Schulze rule.
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Solution
- Generally, the greater the valency of the flocculating ion added, the greater is its power to cause precipitation. This is known as the Hardy–Schulze rule.
- In the coagulation of negative sol, the flocculating power follows the following order:
Al3+ > Ba2+ > Na+ - Similarly, in the coagulation of positive sol, the flocculating power is in the following order:
\[\ce{[Fe(CN)_6]^{4-} > PO_4^{3-} > SO_4^{2-} > Cl^-}\]
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