Description of experiment
Below follows a plain text transcript of the selected experiment.
Needed compounds:
-----------------
hydrogen peroxide : H2O2
sodium hydroxide : NaOH
vanadium pentoxide : V2O5
Class:
------
elem=V,O
coordination
redox
Summary:
--------
Vanadium (V) compounds form yellow compouds with hydrogen peroxide in
alkaline environments, with strong solutions and very high alkalinity grey
and blue compounds are formed, which, however, decompose easily.
Description:
------------
Dissolve some vanadium pentoxide in a warm solution of NaOH, until the liquid
is colorless. Let this liquid cool down to room temperature.
Add some hydrogen peroxide (30% by weight) and shake well: The liquid becomes
yellow and remains clear.
Add much more hydrogen peroxide (30%): The liquid becomes much darker and
attains a dark grey color. The hydrogen peroxide decomposes, the liquid
produces many small bubbles and starts foaming a little. The liquid, sticking
to the glass, even appears to be blue.
Dilute the liquid with a lot of water: The liquid becomes light grey and
slowly evolves oxygen.
Wait for appr. 12 hours: The grey liquid has become yellow.