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Help!! What is the colour of Barium Phosphate? (1 Viewer)

davemate03

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Hey guys, I realised that the precipitation tests that I learnt are really wierd compared to everyone elses e.g. Test for Phosphate ions, add ammonium molybdate?

I looked up my textbook and it says to add OH to make it alkaline and then BaPO4. However, it doesn't say anything about the colour??

Can anyone help?
 

Fortify

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For phosphate, add silver nitrate solution and it'll form a yellow precipitate (silver phosphate).
 

davemate03

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Oh cheers mate, what about Lead? I'm fairly sure it goes yellow with something as well....
 

Divinity_

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Add HCl or salt that contains Chloride, it forms white ppte of lead chloride.
 

tizona

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according to the solubility table, chlorines, bromides and iodides are soluble except for lead, mercury and silver.

so adding chloride or iodide wont make a difference, but iodide is preferable because it forms a yellow precipitate instead of the normal white precipitate and thus would be easily distinguished from other cations.
 

Fortify

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according to the solubility table, chlorines, bromides and iodides are soluble except for lead, mercury and silver.

so adding chloride or iodide wont make a difference, but iodide is preferable because it forms a yellow precipitate instead of the normal white precipitate and thus would be easily distinguished from other cations.
But then Pb2+ is the 1st ppte out according to this:
 

lychnobity

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Hey guys, I realised that the precipitation tests that I learnt are really wierd compared to everyone elses e.g. Test for Phosphate ions, add ammonium molybdate?

I looked up my textbook and it says to add OH to make it alkaline and then BaPO4. However, it doesn't say anything about the colour??

Can anyone help?
The ammonium molybdate method is one based on colour.

Ok, to test for phosphates using this method, add acid to the sample, then add ammonium molybdate. If phosphate is present, it'll turn yellow.
 

harry4

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i learnt to test for phosphate you make the solution alkaline by adding NH3 and then add Ba2+ and you get a white ppt
 

mR sinister

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Quick and easy method:
Add HNO3
and yellow ppt forms.

:D goodluck tommorow
 

ajay098

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The ammonium molybdate method is one based on colour.

Ok, to test for phosphates using this method, add acid to the sample, then add ammonium molybdate. If phosphate is present, it'll turn yellow.
if u are gonna add H+/molybdate, u MUST heat it
 

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