Question
Write notes on : Hardy-Schulze rule
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Answer
Hardy-Schulze rule:
i. Generally, greater the valency of the flocculating ion added, greater is its power to cause precipitation. This is known as Hardy-Schulze rule.
ii. In the coagulation of negative sol, the flocculating power follows the following order:
$Al^{3+} > Ba^{2+} > Na^+$
iii. Similarly, in the coagulation of positive sol, the flocculating power is in the following order:
$[Fe (CN)_6]^{4-} > PO_4^{3-} > SO_4^{2-} > Cl^–$
i. Generally, greater the valency of the flocculating ion added, greater is its power to cause precipitation. This is known as Hardy-Schulze rule.
ii. In the coagulation of negative sol, the flocculating power follows the following order:
$Al^{3+} > Ba^{2+} > Na^+$
iii. Similarly, in the coagulation of positive sol, the flocculating power is in the following order:
$[Fe (CN)_6]^{4-} > PO_4^{3-} > SO_4^{2-} > Cl^–$
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