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a level paper help reactions

for 10.1 I got the negative ions correct e.g. cl-, but for the first two how do you derive the metal part of the compound? Also, under what reaction/test is the reaction with hcl come under? thanks https://filestore.aqa.org.uk/resources/chemistry/AQA-74051-SQP.PDF
check out th topic after transition metals “ions in aqueous solutions”
from what source? my tb doesn't have that topic
Original post by theowinn
check out th topic after transition metals “ions in aqueous solutions”
Reply 3
For the first one (Q), the answer is calcium or magnesium bromide. You can work out the Br because AgNO3 gives a pale cream precipitate. You can work out the Mg or Ca because NaOH gives a white precipitate, this part is really evil and obscure, it comes from one of the test tube reactions in required practical 4 (attached picture), in an exam, I reckon hardly any students would get this!!!

For the second one (R), the answer is aluminium chloride. You can work out the Cl because AgNO3 gives a white precipitate. You can work out Al because Na2CO3 gives a white precipitate with bubbles of gas (CO2), this is one of the transition metal reactions you need to know ( I have linked the table of all the reaction below).

For the final one (S), the answer is iron(III) sulfate. You can work out the sulphate because Bacl2 gives a white precipitate (BaSO4 is formed, it is very insoluble). As for the Iron (III), Na2CO3 gives a brown precipitate with bubbles of gas (CO2), this is another one of the transition metal reactions you need to know.

I'm not sure about why the reactions with HCL are there, I wonder whether it is just to throw people off???

https://filestore.aqa.org.uk/resources/chemistry/AQA-7405-REACTIONS-OF-METAL-IONS.PDF
thanks a lot. it that aqa link you provided for the new or old spec, as on the second page it mentions colours of vanadium species which I don't think i've learnt about?
Original post by Ezooner
For the first one (Q), the answer is calcium or magnesium bromide. You can work out the Br because AgNO3 gives a pale cream precipitate. You can work out the Mg or Ca because NaOH gives a white precipitate, this part is really evil and obscure, it comes from one of the test tube reactions in required practical 4 (attached picture), in an exam, I reckon hardly any students would get this!!!

For the second one (R), the answer is aluminium chloride. You can work out the Cl because AgNO3 gives a white precipitate. You can work out Al because Na2CO3 gives a white precipitate with bubbles of gas (CO2), this is one of the transition metal reactions you need to know ( I have linked the table of all the reaction below).

For the final one (S), the answer is iron(III) sulfate. You can work out the sulphate because Bacl2 gives a white precipitate (BaSO4 is formed, it is very insoluble). As for the Iron (III), Na2CO3 gives a brown precipitate with bubbles of gas (CO2), this is another one of the transition metal reactions you need to know.

I'm not sure about why the reactions with HCL are there, I wonder whether it is just to throw people off???

https://filestore.aqa.org.uk/resources/chemistry/AQA-7405-REACTIONS-OF-METAL-IONS.PDF
Reply 5
It’s definitely the new spec

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