Chemistry paper 12 discussion!!!!!!!!!!

[gary221]

no its not i checked my book the core of the cables is made of steel and aluminum around the steel so the cables don't bend and for sure platinum for electrodes but aluminum for cables

Ahhh.. Just read it now :/

Well that is 1 wrong ):

Hey xishtar, but copper cables are also used

exactly!!

i think most wires r made of Cu thts wht it said in my book

 

[Gunner1995]

Its Nitrates ONLY! And its CaO and O2. NOT HEAT. so A.

 

[gary221]

Did the question say the core, or outside of the cable?

i think it said core!

 

[gary221]

guys..

If the question mentions the word "core" then it means that aluminum is used as a conductor
If the question doesn`t mention the word "core" then it means that copper is used as a conductor

so.. does the question mention that word "core"

but Cu is also used for electrical wiring
how wre we expected to know which is correct???

 

[gary221]

Its Nitrates ONLY! And its CaO and O2. NOT HEAT. so A.

hey how come its nitrates???
the ques only mentioned the cations, how can it be only nitrates???
it could be anything!!

 

[gary221]

As far as I remember ... the 1st 2 options didn`t mention ACID

and "C" mentioned that all the alloy will dissolve in HCL which is WRONG because copper doesn`t dissolve
so "D" might be the correct response as only zing reacts with HCL

yup thts wht i wrote
the 1st option ws tht brass can be represented by a chemical formula,which ws wrong, wasnt it???
and the 2nd one ws tht zinc and Cu react or sth

 

[gary221]

what was the HCl question again plz

which HCl ques??

 

[Keeemoman]

Its Nitrates ONLY! And its CaO and O2. NOT HEAT. so A.

hey how come its nitrates???
the ques only mentioned the cations, how can it be only nitrates???
it could be anything!!

Since they mentioned A solution conains barium and silver ions
This means if there is sulphate there will be precipitate BaSO4 same for AgCl

But as for the steel question it is for 100% sure heat is needed as you pass molten iron which is heated as its state is converted....
This is written in the book brought by IGCSE cambridge university and not endorsed

 

[steaminferno]

guys..

If the question mentions the word "core" then it means that aluminum is used as a conductor
If the question doesn`t mention the word "core" then it means that copper is used as a conductor

so.. does the question mention that word "core"

but Cu is also used for electrical wiring
how wre we expected to know which is correct???

The question asked about overhead cables. Those cables are made of Aluminum and Iron. Aluminum is used because it is a good conductor of electricity and has a low density. Steel is used as the core to give the cables strength.

Copper is a good conductor of electricity and is therefore used in electrical wiring. It is not used in overhead power cables.

guys..

If the question mentions the word "core" then it means that aluminum is used as a conductor
If the question doesn`t mention the word "core" then it means that copper is used as a conductor

so.. does the question mention that word "core"

If I remember correctly the question didn't mention the word core. Even if the word 'core' was their copper isn't used as the core for overhead powerlines. Steel is used.

 

[gary221]

Its Nitrates ONLY! And its CaO and O2. NOT HEAT. so A.

hey how come its nitrates???
the ques only mentioned the cations, how can it be only nitrates???
it could be anything!!

Since they mentioned A solution conains barium and silver ions
This means if there is sulphate there will be precipitate BaSO4 same for AgCl

But as for the steel question it is for 100% sure heat is needed as you pass molten iron which is heated as its state is converted....
This is written in the book brought by IGCSE cambridge university and not endorsed

 

[Keeemoman]

Eveen if they didnt mention it is still aluminium although I wrote copper which is wrong. They mentioned overhead cables

Gary I am really sorry but I had to do that cause u still hve the last chance so hoped learned from your mistake

 

[gary221]

Eveen if they didnt mention it is still aluminium although I wrote copper which is wrong. They mentioned overhead cables

Gary I am really sorry but I had to do that cause u still hve the last chance so hoped learned from your mistake

ur correct
if i get 36/40 will i get an A???

 

[Keeemoman]

Eveen if they didnt mention it is still aluminium although I wrote copper which is wrong. They mentioned overhead cables

Gary I am really sorry but I had to do that cause u still hve the last chance so hoped learned from your mistake

ur correct
if i get 36/40 will i get an A???

Yup man for sure u will get it even if 34 or also could reach to 33 and 32
So cheer up cocentrate in paper 3 cause its damn important
Wish you a good luck :good: :good: :good: :good: :good: :good:
:beer: :beer: :beer: :beer:

 

[gary221]

thnx !!!!
all the best to u too!!!


hope we all get A* Insha Allah!!!! :good: :good: :good:

 

[xIshtar]

The paper had some trickier questions than M/J 10, where 29 was for an A, so you have a definite A, if not a high A.

According to you guys, I have 38/40

 

[Keeemoman]

The paper had some trickier questions than M/J 10, where 29 was for an A, so you have a definite A, if not a high A.

According to you guys, I have 38/40

The same here

 

[xIshtar]

The paper had some trickier questions than M/J 10, where 29 was for an A, so you have a definite A, if not a high A.

According to you guys, I have 38/40

The same here

If I remember, we had the same for Physics P1 too?

 

[Aahmsil]

Huh ?!?!?!?!

Its Nitrates ONLY! And its CaO and O2. NOT HEAT. so A.

hey how come its nitrates???
the ques only mentioned the cations, how can it be only nitrates???
it could be anything!!

Since they mentioned A solution conains barium and silver ions
This means if there is sulphate there will be precipitate BaSO4 same for AgCl

But as for the steel question it is for 100% sure heat is needed as you pass molten iron which is heated as its state is converted....
This is written in the book brought by IGCSE cambridge university and not endorsed

@Keemoman: So silver nitrate or barium nitrate will be liquid ???

 

[gary221]

but tht Al n Cu thing???
tht was too tricky!!!

 

[She7taman]

Re: Huh ?!?!?!?!

@Keemoman: So silver nitrate or barium nitrate will be liquid ???

Yes, because barium nitrate and silver nitrate are both soluble. Anything else and there will be one of them that is insoluble.

As for the steel question, I wouldn't be so sure that heat is required. Heat is required in the *first* step, where you have your iron ore and you're extracting it. No one ever said you needed heat when you were removing the impurities from pig iron.