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IGCSE Chemistry salt preparation

Why is the answer B?
Why can't we prepare potassium sulfate and sodium sulfate by this method? For example, we could react NaO (a solid) with sulfuric acid and obtain sodium sulfate.
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(edited 1 year ago)
Original post by S0303
Why is the answer B?
Why can't we prepare potassium sulfate and sodium sulfate by this method? For example, we could react NaO (a solid) with sulfuric acid and obtain sodium sulfate.
[post="97790584"]save[/post]


By the looks of the diagrams (which should match up to your practical method) is to crush a solid (1) add it to the sulfuric acid and heat (2) any excess insoluble reactant (from 1) is filtered off, the filtrate containing your final product is warmed (4) to yield you pure salt.

The Q is about the solubility rules.

Do you know whether the chemicals in A-D are soluble or not?

(also Na2O is Na2O not NaO)
(edited 1 year ago)
The question is which reactants can be dissociated in sulfuric acid in the last step (4) to get the salt and thus makes sense for a preparation. Copper may have the least reactivity for these steps, but it makes a difference whether the acid is diluted or concentrated.
(edited 1 year ago)

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