CHEM P42 GT and paper discussion

[asenfire]

ki aey?

yes

 

[A*(a*)]

i did calculate the remaining OH ions in the initial part but I am telling abt the sketch, where will the PH end? would it not end at NaOH ph?

 

[A*(a*)]

any other qs u remember?

 

[saadgujjar]

any other qs u remember?

we ar not supposed to memtion the stop codon In amino acid sequence

 

[asenfire]

what was the value 2.88 can anyone remember

 

[asenfire]

what was the value 2.88 can anyone remember

i got it but forgot

 

[kruti]

i got it but forgot

pH of acid 2.88. pH of OH - = 12.8

 

[saadgujjar]

ph of ethanoic acid

 

[kruti]

ph of ethanoic acid

I think it was 2.88

 

[asenfire]

can anyone tell me how does CIE use the weighting percentages, i really wish to know it. Sry if it is off-topic

 

[A*(a*)]

yes i didnt mention. mutation was another ans.

 

[Vidushi Kaushali]

first blue then pale blue ppt then deep blue of Cu(NH3)4.

thanks.....

 

[A star]

E which was given was -0.13 and its for standard conditions and 1 molar conc. But in saturated sol of pbcl2 the conc was lesser than 1 molar so obviously E will be more negative.

no my friend you had to utilise the equation given in the data booklet for the reduction potential of lead, it will become more positive since the reaction would move backwards!!!!!!!

 

[A star]

the reaction forward has a negative potential so backward will ofcourse be more positive hence the formulae E0=Er-El cause to reverse the reduction equation you have to reverse the potential hence making the Eo value more positive. . its from recent years and i spent 10 minutes on it so I KNOW

 

[saadgujjar]

the reaction forward has a negative potential so backward will ofcourse be more positive hence the formulae E0=Er-El cause to reverse the reduction equation you have to reverse the potential hence making the Eo value more positive. . its from recent years and i spent 10 minutes on it so I KNOW

i disagree

 

[A star]

i disagree

then pleasee the recent year past papers. they have done the same thing. My logic as I said is you ae decreasing the concentration of Pb2+ ions the reaction will go in reverse to counteract the change in equilibirium (le chatliers principle) if the forward value is negative so it will just go the endothermic way(backward)
p.s ( i havent found a single mistake so if it is i will only loose two marks so chears

 

[saadgujjar]

 

[saadgujjar]

this is from oct 12 p42

 

[A star]

this is from oct 12 p42

isae kia hae maenae is lea yae logic lagae hae. is mae equation sae bhi yahi logic lag rah hae

 

[saadgujjar]

isae kia hae maenae is lea yae logic lagae hae. is mae equation sae bhi yahi logic lag rah hae

ap k paas coursebook ha???us sa dkh lo jitna reacton backward hoga utni E negative