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Question
Which of the following electrolytes will have maximum coagulating value for AgI/Ag+ solution?
Options
Na2S
Na3PO4
Na2SO4
NaCl
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Solution
Na3PO4
Explanation:
To Hardy-Schulze law, the greater the charge on anion, the greater will be its coagulating power.
| Electrolytes | Anionic part | Charge on anion |
| \[\ce{Na2S}\] | \[\ce{S^{2-}}\] | 2 |
| \[\ce{Na3PO4}\] | \[\ce{PO^{3-}_{4}}\] | 3 |
| \[\ce{Na2SO4}\] | \[\ce{SO^{2-}_{4}}\] | 2 |
| \[\ce{NaCl}\] | \[\ce{Cl^{-}}\] | 1 |
Here, \[\ce{PO^{3-}_{4}}\] have highest charge. Hence \[\ce{PO^{3-}_{4}}\] have height coagulating power.
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