What is Benedicts solution?

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UG

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What is Benedicts solution?
« on: 08/02/2009 01:34:55 »
[?][?] Can u tell me what it is?

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Offline Chemistry4me

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What is Benedicts solution?
« Reply #1 on: 08/02/2009 01:40:47 »
Benedict's solution contains aqueous copper (II) ions Cu2+ (which gives the reagent a blue colour) in alkaline conditions. To prevent the Cu2+ from precipitating out as Cu(OH)2, the Cu2+ is complexed with citrate ions.

When Benedicts solution is added to an aldehyde and warmed, a reddish brown ppt of copper(I) oxide Cu2O forms:

For example:

CH3CHO + 4OH- + 2Cu2+ > CH3COOH + Cu2O + 2H2O

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UG

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What is Benedicts solution?
« Reply #2 on: 08/02/2009 01:46:55 »
When Benedict's solution oxidizes ethanal to ethanoic acid, an ion is the oxidant.
a) What is its name and formula
b) what is the color change
c)Whats the reduction half-equation

Can sombody tell me  [?]

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Offline Chemistry4me

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What is Benedicts solution?
« Reply #3 on: 08/02/2009 01:48:07 »
This sounds exactly the same as the example I gave! [:D]

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Offline Chemistry4me

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What is Benedicts solution?
« Reply #4 on: 08/02/2009 01:53:11 »
The ion is copper (II) ion Cu2+
The blue solution turns to a reddish-orange precipitate (Cu2O)
The reduction half-equation is:

Cu2+ + H2O + e- > Cu2O + 2H+
 

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UG

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What is Benedicts solution?
« Reply #5 on: 08/02/2009 03:09:21 »
Thank you [;D]