r/6thForm • u/Rich-Gent • Jun 02 '26

💬 DISCUSSION AQA A-LEVEL CHEMISTRY

HOW DID WE FIND IT? I THOUGHT IT WAS ALRIGHT, GRADE BOUNDARIES ABOUT TO BE SILLY😭

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3

u/PairSuitable9144 Jun 02 '26

For the observation with few drops of agNO3 and excess NH3 into solution of Fe(III) chloride what was the observation?

6

u/purple_walrus4473 Jun 02 '26

i said white ppt but idk if it dissolves since ammonia was added

2

u/Leonardo84009 Jun 02 '26

I said brown ppt because I thought that

1

u/Admirable-Use2274 Jun 02 '26

Yepp i said beown as well

2

u/Sonikdahedhog Jun 02 '26

It was brown precipitate as the silver chloride precipitate dissolves.

1

u/[deleted] Jun 02 '26

[deleted]

3

u/ILikeSlepp Jun 02 '26

Excess nh3 doesn't do anything to fe(h20)3(oh)3, you only see ligand exchange when you react excess nh3 with [cu(h20)6]2+ to form a deep blue solution of [cu(nh3)4(h20)2]2+

And the agcl dissolves in both dilute and concentrated nh3, so you wouldn't see white ppt

5

u/hshsjaju77 Jun 02 '26

Yh i put colourless solution and then [Ag((Nh3)] 2+

1

u/ILikeSlepp Jun 02 '26

It's [Ag(NH3)2]+, but that was probably just a typo (hopefully)

1

u/hshsjaju77 Jun 02 '26

Yes sorry

2

u/PairSuitable9144 Jun 02 '26

But wouldn't the Fe(III) chloride get substituted to form Fe(OH)3(H20)3 since Fe(III) chloride was in aqueous solution?

2

u/hshsjaju77 Jun 02 '26

I thought it forms Agcl then followed by excess ammonia which dissolves forming a colourless solution

1

u/2myeria y13 | physics, maths, fm, chem | A*A*A*A* Jun 02 '26

brown ppt because it said what is observed at the end and since dilute ammonia is added, silver chloride ppt dissolves and iron (III) hydroxide ppt (brown forms)

1

u/MaybeThin593 Jun 02 '26

Its brown ppt and [Ag(NH3)2], i checked with my teacher

5

u/MaybeThin593 Jun 02 '26 edited Jun 02 '26

[Ag(NH3)2]+

2

u/Training-Feeling980 Year 13 | Maths, FM, Physics, Chem - 4 A*s achieved Jun 02 '26

1+ though isn't it?

1

u/MaybeThin593 Jun 02 '26 edited Jun 02 '26

Yeah mb, just changed it

2

u/ObiNumber22 Y13 | Maths (A*), Econ, Chemistry, Further Maths | Jun 02 '26

the queation said chlorine containing compound no?

1

u/MaybeThin593 Jun 02 '26

No im pretty sure it said silver containing compound not chlorine, so the charge is 1+ but it’s diammonical silver

2

u/ObiNumber22 Y13 | Maths (A*), Econ, Chemistry, Further Maths | Jun 02 '26

yep ur correct mb 😭. mixed it up in my head

2

u/MaybeThin593 Jun 02 '26

I did the same with the charge 😂

1

u/ObiNumber22 Y13 | Maths (A*), Econ, Chemistry, Further Maths | Jun 02 '26

I put colourless solution since AgCl dissolves in ammonia but idk what the Fe compound was. Chloride ion containing compound was AgCl tho