Description of experiment
Below follows a plain text transcript of the selected experiment.
Needed compounds:
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tartaric acid : HOOC CHOH CHOH COOH
hydrochloric acid : HCl
antimony sesquioxide : Sb2O3
Class:
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elem=Sb
coordination
Summary:
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Antimony (III) is supposed to form a stable complex with tartaric acid or
tartrates. This experiment does not show such behaviour. Apparently the
conditions must be selected carefully in order to create the antimony/
tartrate complex.
Description:
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Sequence 1:
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Add some solid Sb2O3 to some hydrochloric acid (appr. 5% by weight): The solid
partly dissolves, the liquid becomes white and turbid.
Add some tartaric acid and shake well: The acid dissolves, the liquid does
not become clearer.
Sequence 2:
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Add some solid Sb2O3 to some hydrochloric acid (appr. 4% by weight): The solid
partly dissolves, the liquid becomes turbid.
Add much water: The liquid becomes even more turbid, it looks like milk.
Add some tartaric acid: The acid dissolves, but the liquid does not appear
to become much clearer.
Boil the liquid for a while: Now the liquid becomes clearer, but some little
crystals separate from the liquid. These little crystals stick to the glass.