A chemist in a water treatment plant needs to prepare barium sulfate for use in medical imaging. She has solutions of barium chloride and sodium sulfate available.

Which statement correctly describes the preparation of barium sulfate?

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Question

A chemist in a water treatment plant needs to prepare barium sulfate for use in medical imaging. She has solutions of barium chloride and sodium sulfate available.

Which statement correctly describes the preparation of barium sulfate?

Accepted Answer

Mix the two solutions, filter the precipitate, wash with distilled water and dry — Award 1 mark for correct precipitation method. Barium sulfate is insoluble and forms immediately when the two solutions are mixed. The precipitate must be filtered, washed to remove soluble impurities (sodium chloride), and dried. A is incorrect because barium sulfate is insoluble and will not dissolve to form crystals on evaporation. C is incorrect because no indicator is needed for precipitation reactions. D is incorrect because decanting alone will not produce a pure, dry sample.

Answer

Mix the two solutions and evaporate to obtain barium sulfate crystals

Answer

Add excess sodium sulfate to barium chloride and decant the liquid

Answer

Titrate barium chloride with sodium sulfate using a suitable indicator

Answer

Mix the two solutions, filter the precipitate, wash with distilled water and dry

One real Chemistry question.No signup. 30 seconds.

One real Chemistry question.
No signup. 30 seconds.