cnidocyte
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Testing for urea
I boiled a solution of NH2NO3 and urea that I got from an instant cold pack in water for a long time and at around 5C, a lot of white solid
crystallised out of the water. I'm not fully sure that the urea is gone though. Carbonyl groups significantly lower the basicity of amino groups
attached to them but since theres 2 amino groups in urea would it still be basic enough to be able to identify it by checking the pH?
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Magpie
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Do you mean NH4NO3 and urea?
According to Baker MSDSs pH for NH4NO3 is 5.4 and that for urea is 7.2.
What was the pH before and after the crystal removal?
The single most important condition for a successful synthesis is good mixing - Nicodem
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cnidocyte
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Forgot to test the pH before, its at about 6 now. Definitely below 7. This isn't a good way to test for urea, I thought urea would be a lot more basic
than that.
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entropy51
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Berthelot's reaction using alkaline hypochlorite and phenol gives a blue color with urea. It may be too sensitive for your purposes, however.
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Paddywhacker
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You may have urea nitrate.
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TheOrbit
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i know u can check for urea by buiret test "on solid "
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