• We need your support!

    We are currently struggling to cover the operational costs of Xtremepapers, as a result we might have to shut this website down. Please donate if we have helped you and help make a difference in other students' lives!
    Click here to Donate Now (View Announcement)

Biology; Chemistry; Physics: Post your doubts here!

FLRNAB

FLRNAB

Messages
657
Reaction score
1,447
Points
143
exploded diper said:
so u see we have moles for iron sulphate which are (f)
we have moles of water which are (i)
this (i)moles are for this(f)moles...and we need water moles for one feso4.......
so divide (1) by (f) which cums to be 7.18.....so round it of to 7.......
Click to expand...
Nope flew over my head. I need the intuition behind it.
 
exploded diper

exploded diper

Messages
1,665
Reaction score
2,400
Points
273
http://papers.xtremepapers.com/CIE/...l O Level/Chemistry (5070)/5070_s11_qp_42.pdf
q) 6....zinc is in peices and zinc is in powder...still the other reaction with peices is faster....
when metals are deposited on cathode will they always form a sludge.....
do we have to write gas syring or syringe.....<----- i know a sillly question
vats the use of proclein chips in cracking.......


FLRNAB said:
Nope flew over my head. I need the intuition behind it.
Click to expand...

u see tht it is asking the moles of water in one mole of the whole compound.....
while in the previous ones we know the moles of water (which are 0.158) in 0.0223 feso4....
so as per unitary method.....for one it would be 1*0.158/0.0223.......which is 7.09....and as moles are always to be written as integers it becomes 7
 
Abdul Hanan

Abdul Hanan

Messages
499
Reaction score
584
Points
103
Faizan Muhammmad said:
noo iron 3 sulphate is yellow actually
what I am worried is we have learnt iron 3 compounds to be red
so I was saying how is it yellow
Click to expand...
this is the reason that marking scheme giving us an option between all 3 colours yellow [iron(iii)sulfate],green (iron(ii)sulfate),and colourless as solution is very dilute and colours barely visible.
all questions (2004-2013) including this iron(ii)sulfate and potassium permanganate titration (only) have the same colour change.(colourless to purple). :)
 
FLRNAB

FLRNAB

Messages
657
Reaction score
1,447
Points
143
exploded diper said:
http://papers.xtremepapers.com/CIE/Cambridge International O Level/Chemistry (5070)/5070_s11_qp_42.pdf
q) 6....zinc is in peices and zinc is in powder...still the other reaction with peices is faster....
when metals are deposited on cathode will they always form a sludge.....
do we have to write gas syring or syringe.....<----- i know a sillly question
vats the use of proclein chips in cracking.......




u see tht it is asking the moles of water in one mole of the whole compound.....
while in the previous ones we know the moles of water (which are 0.158) in 0.0223 feso4....
so as per unitary method.....for one it would be 1*0.158/0.0223.......which is 7.09....and as moles are always to be written as integers it becomes 7
Click to expand...
Got it now. Thanks bro
 
You must log in or register to reply here.
Top