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Biology; Chemistry; Physics: Post your doubts here!

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I think i already said that if final twmp. is 90 how is it not possible, 90*C does not exceed boiling point of water , read the whole question not just the marking scheme GENIUS:p
bhai dafa kr ab.:D
paper kesa hua? and can you relate the answers of the questions you remember.
 
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I wrote 1st titration vol 25.3 as it was 25.2 which slightly changed my answer of average further my answers to part a b c were change
for example
.000506 mol but i wrote .000507
how much max i will be penalised plzzzz help
 
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It was 3 , 1st 3rd 4th test tube

which ester diagram we have to make structure only

There was no reaction in the 1st and 4th test tube, as there was a copper rod in a solution of mg ions in 1st test tube, dont remember the fourth but pretty sure there was no reaction

*diagram my bad :oops:
 
Messages
105
Reaction score
116
Points
28
I wrote 1st titration vol 25.3 as it was 25.2 which slightly changed my answer of average further my answers to part a b c were change
for example
.000506 mol but i wrote .000507
how much max i will be penalised plzzzz help

in the mark schemes they require prescise anwers , as for the titration vol i think if you mess up one volume they consider it all wrong .
 
Messages
122
Reaction score
55
Points
38
There was no reaction in the 1st and 4th test tube, as there was a copper rod in a solution of mg ions in 1st test tube, dont remember the fourth but pretty sure there was no reaction

*diagram my bad :oops:
yes, of course there was a reaction in 4th. As far as I can remember, there was magnesium rod dipped in Cu2+ solution. I triple checked. 3 was the right answer.
 
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mass of CaCO3 used was 1.8 g, percentage of iron was 8.7% in mixture, titration average volume was 25.3. Magnesium Ribbon was silvery white. Emprical formula was C3H8O. Molecular formula was C3H7OH. And ester was propyl prponate. anything more?
 
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in the mark schemes they require prescise anwers , as for the titration vol i think if you mess up one volume they consider it all wrong .
I am saved, by this i only lost appx. 2 marks in whole paper
yes, of course there was a reaction in 4th. As far as I can remember, there was magnesium rod dipped in Cu2+ solution. I triple checked. 3 was the right answer.
You are right i also did this, only 2nd reaction was not feasible
 

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What was the answer of colour change in titration question

green to pink im sure of it ;)

mass of CaCO3 used was 1.8 g, percentage of iron was 8.7% in mixture, titration average volume was 25.3. Magnesium Ribbon was silvery white. Emprical formula was C3H8O. Molecular formula was C3H7OH. And ester was propyl prponate. anything more?

Damn! i wrote the same thing for the empirical formula and the molecular formula : C3H7OH is it wrong ?:eek:
 
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