Strange observation during ascorbic reduction of copper(II) sulfate
so here is a simple experiment of which I'm not sure how to explain it.
Experiment 1:
1 g copper(II)sulfate together with 1 g of sodium chloride was dissolved in 10 ml water. When dissolved, 0.4 g (~0.55) molar eqvts relative to
copper(II)sulfate) of ascorbic acid was added at once. After a few minutes at 40 C, a white precipitate of presumably copper(I)chloride was formed,
with colourless supernatant, indicating all copper(II) was reduced to copper(I).
Experiment 2:
1 g copper(II)sulfate was dissolved in 10 ml water. When dissolved, 0.4 g (~0.55 molar eqvts relative to copper(II)sulfate) of ascorbic acid was
added at once. The solution became a bright green colour and was stirred for several minutes at 40 C. Then 15 ml of ice cold ethanol was added,
precipitating a very light blue compound (almost white). Upon filtering, washing and drying, it becomes a more white in colour, but still with light
blue shade. When redissolved in water, it dissolves with a light blue colour. When sodium chloride is added, no copper(I)chloride is produced, also
not upon heating the solution further.
The compound produced seems like unchanged copper(II)sulfate or possibly a complex with ascorbic, any ideas how these experiments can be explained?
[Edited on 17-3-2018 by nitro-genes]
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