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Ion-pair formation constant ( K AgPic in mol −1 dm 3 ) of silver picrate (AgPic), those ( K AgLPic ) of its ion-pair complexes (AgLPic) with crown ethers (L) and complex formation constants ( K AgL ) of Ag + with L (15-crown-5 ether (15C5) and benzo-15C5) in water (w) were determined potentiometrically at 25 °C. Compounds used as L were 18-crown-6 ether (18C6), its benzo-derivative (B18C6) and the two 15C5 derivatives. Extraction constants ( K ex in mol −1 dm 3 ) of AgPic with L (15C5, 18C6, B18C6) from acidic w-phases into either C 6 H 6 or CHCl 3 were recalculated from K AgPic , K AgL , K AgLPic and data opened in previous papers. Thus obtained K ex was divided into five component equilibrium constants containing K AgL and K AgLPic anew. Then, contributions of the component constants, K AgL , K AgLPic and distribution constants of AgLPic between the w- and C 6 H 6 -phases, to K ex were discussed and compared with corresponding extraction systems of NaPic and KPic with18C6. |
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