chemistry 34 threshold

[omerkc1]

Yep it was carbonate..................

 

[EzioAuditre]

same volume was used in order to keep the depth same so that it always disappear when the same amount ov sulfur has been formed
2003 may/june paper 3

 

[grumpy]

guys i got injured during the practical mat poocho kesa.
and i left 4 marks question so i did 36 marks paper and i am expecting 30 or above .
the head examiner called me after the paper asked me few questions and then wrote compensation letter for me.
what do you all think about this.
will i get some marks out of 4 marks left.
the questions he asked was about the practical and he was pleased to listen my answers.

 

[Sannikutti]

Guys i had a question
why sodium dont react with easter
pls answer fast
thnx

 

[grumpy]

simply there is no H+ IN ESTER

 

[farrukh]

guys...wasn't the anion supposed to be sulfite...
if u see qualitative analysis notes...an anion that gives white ppt that dissolves in dil acid is sulfite...and the question made us do this test and result was positive..

 

[omerkc1]

nope.......its carbonate....................cuz sulpide doesnt give off CO2...................

 

[Sannikutti]

Guys
Should have we measured the time to nearest second rite???
anss pls thnx

 

[fahadii92]

yes to nearest sec.... no ecimal places !

 

[Sannikutti]

THaaaaaaaankkkkkkkkkkkkkssssssssssssssssss FAAAAAAAAAAAADIIIIIIIIIIIIIIIIII

 

[Sannikutti]

@farroukh
Look bro white ppt was due to PbCl2 not because SO4 ion

 

[EzioAuditre]

for the time question i guess there will be only 2 mark for accuracy and 3 for units,time,2 further readings,1/time,volumes of the solutions and water,table mark

 

[princesszahra]

plz dont discuss the paper, just guess the threshold, i say around 28..... it was tough :

chk this one
viewtopic.php?f=26&t=8798

 

[farrukh]

@farroukh
Look bro white ppt was due to PbCl2 not because SO4 ion

there was no chloride ion prsent...
when we added barium chloride to fb11 white ppt was formed that disslved in excess dil acid...
thts why i wrote sulfite

 

[asdfg12345]

If i wrote NaOh and Nh3 for the reagents, will i lose like all the marks ?
As for the identification of cations, i wrote both Al and Pb for fb7 and 9.
is it a gone case?

 

[grumpy]

If i wrote NaOh and Nh3 for the reagents, will i lose like all the marks ?
As for the identification of cations, i wrote both Al and Pb for fb7 and 9.
is it a gone case?

i also wrote like these two reagents and one extra one hcl.
how many marks will i loose.
i got the conculusions right.