testing for ions

[abbadell]

Can someone please help me with these questions.
If you are testing for cations. Suppose you perform the test for copper before that for lead. Would you be able to successfully identify whether copper was present. If testing for anions and added the barium chloride to test for sulfate ions before you had tested for chloride ions, would you be able to identify successfully whether sulfate was present.

 

[Nakashima]

Copper forms a blue precipitate with hydroxide. Lead also forms a precipitate with hydroxide. If you had a solution that contained either lead or copper, you'll be able to tell which it is by the colour of the precipitate. If there's a possibility that both were present, then test for lead first using chloride.

Why would you want to test for chloride if you know you've just added barium chloride?

Learn your solubility rules and it's all pure logic.

 

[Forbidden.]

Can someone please help me with these questions.
If you are testing for cations. Suppose you perform the test for copper before that for lead. Would you be able to successfully identify whether copper was present. If testing for anions and added the barium chloride to test for sulfate ions before you had tested for chloride ions, would you be able to identify successfully whether sulfate was present.

You are such an awesome person like me who doesnt completely know their solubility rules by heart .. Im just gonna copy it from a sheet


Soluble Ionic Compunds


Group 1 and ammonium

nitrates

acetates (ethanoates)

chlorides, bromides and idodides (except silver and lead ions)

sulfates (except silver, lead, barium, strontium, and calcium ions)

Insoluble Ionic Compunds


carbonates, sulfites and phosphates (except group 1 and ammonium compunds)

hydroxides and oxides(except Group 1, ammonium, barium, strontium and calcium ions)

sulfides (except Groups 1, 2 and ammonium ions)



NOTE: I cant write down the ion configuration, because I cant input exponentials ...

C'mon, you know hydroxides are OH- with a valency of 1 right ? And an Aluminium ion is Al2+ with two extra electrons right ?

 

[Riviet]

NOTE: I cant write down the ion configuration, because I cant input exponentials ...

Type (sup)1+(/sup) but using [ ] brackets around each sup, this will produce a superscript, ie an exponential. You may also like to know that to produce a subscript ie the small numbers in chemical formulae like CH₄, type (sub)1+(/sup) but using [ ] brackets just like for the superscript.

And an Aluminium ion is Al2+ with two extra electrons right ?

I believe it's Al³⁺, as it appears in group 3 of the periodic table.