Chem p33 confirmations

[safeasmothersmilk]

i have to do this. i need some peace of mindddd

what was your percentage by mass of MgSO4? i got 44%
What was contained in FA6? i got NH4+ and Br-
What was contained in FA7? i got carbonate ion and i couldn't find the cation for it :/
What gas was evolved when that powdered Na salt was heated? i got hydrogen
and how did you calculate the moles of Fe2+ in the weighed thing? i got the moles for the fe2+ in the conical flask but how about the next one?

Please bother with this for a minute and reply!

thaaanks

 

[intel1993]

1st one wright
yea it was Nh4+ and Br-
it `was sulpohate and no cation was present...............confirmed........
carbon dioxide was evolved when heated ammonium salt as it was na2co3
last wala yad nahi kya tha.................

 

[msk]

1st one wright
yea it was Nh4+ and Br-
it `was sulpohate and no cation was present...............confirmed........
carbon dioxide was evolved when heated ammonium salt as it was na2co3
last wala yad nahi kya tha.................

it was H2SO4! i saw in the ir myself...though i dint get it!

 

[intel1993]

ya i know it was h2so4 so no cation...................

 

[FrozenFlamez]

barium was the cation in FA7

 

[bilalnadeem]

fa7 was H+ cation and so4 anion or it could be cl-
hydrogen ion confermation was to be done by k2cr2o7 which would probably change to orange green
nd for the fact that fa7 was an acid , since in the very first reaction we had to react fa7 with fa1 which was a salt nd addin a salt to an acid produces effervescence ....

 

[xenvox]

Ba2+ was the cation in fa7

 

[hassam]

tell me wat was ur mass lost in heating....and how u calculated purityyy

 

[princesszahra]

I feel that i am a stupid one!! I never remember any questions after my exams!

 

[utsav156]

1st one wright
yea it was Nh4+ and Br-
it `was sulpohate and no cation was present...............confirmed........
carbon dioxide was evolved when heated ammonium salt as it was na2co3
last wala yad nahi kya tha.................

in FA7 wasnt it cl-????
plz say this is correct

 

[safeasmothersmilk]

tell me wat was ur mass lost in heating....and how u calculated purityyy

i didn't finish the calculations for the first questions, i skipped two of them which included finding moles of the weighed fe2+ and the one after, which was i think finding percentage purity. and what did you get for percentage error involving the uncertainty of the balance?

in the second question regarding MgSO4.7H2O i got 44% as the percentage by mass of MgSO4. i got this by finding the mass of MgSO4 and dividing it by the total mass of the salt in the beginning multiplied by hundred.

 

[pradeep]

i got fA7 Ba as cation! how can it be possible to get 2 diff. cations in the same soln?