Urgent Chem Help - Silver Nitrate!!

it seems to me that the first white ppt is [Ag(H2O)2]+, and this ppt use up all the Ag ions. so when u adding excess ammonia, it is Co that reacts...so get [Co(NH3)6]2+ in the solution.... well dont know if i'm correct, is this an exam question??

yes it's an exam question! ok well i think i'll go with your suggestion then because it has totally confused me

p.s. what's the formula for aqeous silver nitrate? is it [Ag(NO3)(H20)5]+ or something??

And um how did you know that [Ag(H20)2]+ is a white precipitate?

how can [Ag(H20)2]+ be a ppt? because if its charged then surely its in aqueous solution?

If you add [Co(H2O)6]2+ (aq) with aqeous silver nitrate apparently a white precipitate is formed which dissolves when an excess of dilute aqeous ammonia is added to form a solution containing a metal complex ion (is this [Ag(NH3)2]+ ?) ..what is the white precipitate? Is it AgNO(3) ? How does the formula work? Please help Thank you

any idea what the white precipitate is then?

Is this a qu?If it is then can u give the exact question

A crystalline solid A dissolves in water to give a solution containing the metal complex ion B.

Addition of aqeous silver nitrate to this solution gives a white precipitate of C which dissolves when an excess of dilute aqueous ammonia is added to form a soln containing the metal complex ion D.

The solution of A becomes a blue soln containing metal complex ion E when an excess of conc HCl acid is added.

When conc aqueous ammonia is added dropwise to a soln of A, a blue-green ppt F forms. This then dissolves when an excess of ammonia is added to form a pale brown soln containing the metal complex ion G. This pale brown soln becomes dark brown on standing on air and a soln containing the metal complex H is formed.

Ok, well I get
A- CoCl(2)
B- [Co(H20)6]2+
C-AgNO(3) ...?
D-[Ag(NH3)2]+ ...?
E-[CoCl(4)]2-
F-Co(H2O)(4)(OH)(2)
G-[Co(NH3)6]2+
H-[Co(NH3)6]3+

I *think* A-H are correct but I'm not sure about C & D??

H-[Co(NH3)6]3+

I *think* A-H are correct but I'm not sure about C & D??

Its definitely cobalt because of blue-green ppt with NH3 and brown with excess NH3.
I agree with ur A and B,but i think C is AgCl.i Agree with ur D,E,F and G.
I not sure about H though...

Ok thanks So are you saying the Cl from CoCl(2) form with Ag+ ..but then what happens to the NO(3) from AgNO(3)?

I guess its just a spectator ion.

Ok thanks
By the way is AgCl on the chem syllabus anywhere? (i'm on AQA) How did you know it was white? Cheers

If you add [Co(H2O)6]2+ (aq) with aqeous silver nitrate apparently a white precipitate is formed which dissolves when an excess of dilute aqeous ammonia is added to form a solution containing a metal complex ion (is this [Ag(NH3)2]+ ?) ..what is the white precipitate? Is it AgNO(3) ? How does the formula work? Please help Thank you

Hi

ok first off i have NEVER seen a silver in a complex

the white precipitate: Co (NO3)2 (s)

[Co(NH3)4 ] 2+

cobolt is more likely cos it is a d block element!!!!!!!!!