vmelkon
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weak acid problems
I'm reading about weak acid problems and also buffer solutions.
Example: HF is a weak acid and its Ka = 7.2 x 10-4
and it talks about what happens when you add NaF.
It says "recall that a salt dissolves and dissociates completely into ions".
Is that generally true?
Why is it that you have weak acids and weak bases, but no weak salts?
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Magpie
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They are called weak electrolytes. Look in a solubility product table and you will find a few.
The single most important condition for a successful synthesis is good mixing - Nicodem
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DraconicAcid
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Actually, no- the species listed on a table of Ksp values are strong electrolytes. All of the compounds that dissolve will generally ionize
completely.
The difference is due to the nature of the bonding. Ionic bonds (those found in salts) don't stand up to water and its high dielectric constant.
Covalent bonds (those found in acids; despite the low electronegativity of hydrogen, the small size of the hydrogen ion guarantees that the bond will
have significant covalent character) are not broken by water (although such compounds can react with water to protonate it).
That being said, there are some electrolytes with significant covalent character to their bonds- look up "coordination chemistry" in your textbook.
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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