Description of experiment
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experiment.
Needed compounds: ----------------- sodium sulfite : Na2SO3 sulphuric acid : H2SO4 vanadium pentoxide : V2O5
Class: ------ elem=V redox acid/base
Summary: -------- Vanadium pentoxide hardly dissolves in water. In acid it dissolves slightly better, but even then its solubility is small.
Description: ------------ Add some solid V2O5 to water and heat until boiling: The liquid turns pale yellow and becomes slightly turbid. This turbidity does not disappear within a few minutes.
Add some sulfuric acid (appr. 15% by weight): The liquid becomes clear now and it becomes pale yellow (almost colorless).
Add some excess solid sodium sulfite to the pale yellow liquid: The liquid becomes light blue. The smell of SO2 is observed.
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