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Qube
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Homework Statement
Which of the following CAN be made as a pure substance?
Choices are a list of molecular salts.
Homework Equations
According to my teacher the salt cannot be made as a pure substance if the components undergo a large extent acid-base reaction.
The correct choice was [itex]H_{4}NF[/itex] (this can exist as a pure substance).
The Attempt at a Solution
Wait, what?
Can acid-base reactions occur in the solid-state or in the gaseous state? Is this what the problem is implying? I don't see any issue sticking solid ammonium to solid fluoride as long as there is no water present as a solvent.
I thought acid-base reactions occur only in solution.
The correct answer according to my teacher is [itex]H_{4}NF[/itex] and the rationale is that the below reaction is small extent (note that the product acid is stronger than the reactant acid). Thus [itex]H_{4}NF[/itex] can exist as a pure substance.
[itex]H_{4}N^{+} + F^{-} \leftrightharpoons H_{3}N + HF; Extent: small[/itex]