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TBR gives a table of about 24 salts along with their Ksp values. To memorize or not to memorize?
Should I memorize Ksp values?
- Thread starter Rhino1000
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Sounds like an exercise in futility. I wouldn't memorize them.
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Haha, alright. I will refrain.
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I would just stick to knowing why some salts are most stable than others; e.g. consider the silver salts. AgS is much more stable than AgO, for example. Why?
Sulfur, by nature of being less electronegative than oxygen, is a better Lewis base/electron pair donor/nucleophile; the sulfide ion is more willing to "donate" its electrons. Also the sulfide ion should be bigger and has empty 3d valence orbitals which may or may not be accessible to a great extent. Nonetheless, metals, by nature of possessing a large number of valence d-electrons, may be able to increase the stability of the sulfide ion by populating its d-valence.
This Lewis acid/base model seems to get a lot of mileage. Silver is a good Lewis acid, as are many metal cations, because of the poor shielding afforded by the d electrons. Also, the silver cation has an empty 5s orbital. Thus, we can form a sulfide-to-cation sigma coordinate covalent bond.
We may also form a pi-type coordinate covalent bond as the far-away d-electron density "drifts" to empty 3d valence orbitals on the sulfide anion, making the sulfide anion now more nucleophilic than ever.
Sulfur, by nature of being less electronegative than oxygen, is a better Lewis base/electron pair donor/nucleophile; the sulfide ion is more willing to "donate" its electrons. Also the sulfide ion should be bigger and has empty 3d valence orbitals which may or may not be accessible to a great extent. Nonetheless, metals, by nature of possessing a large number of valence d-electrons, may be able to increase the stability of the sulfide ion by populating its d-valence.
This Lewis acid/base model seems to get a lot of mileage. Silver is a good Lewis acid, as are many metal cations, because of the poor shielding afforded by the d electrons. Also, the silver cation has an empty 5s orbital. Thus, we can form a sulfide-to-cation sigma coordinate covalent bond.
We may also form a pi-type coordinate covalent bond as the far-away d-electron density "drifts" to empty 3d valence orbitals on the sulfide anion, making the sulfide anion now more nucleophilic than ever.
