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Chemistry: Post your doubts here!

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ligand exchange occurs... H2O is exchanged for Chlorine so CuCl4-2 complex forms... on adding water the opposite happens
[Cu(H2O)6]2+ + 4Cl - ⇌ [CuCl4]2- + 6H2O

hope this makes sense :)
 
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I have a question > When we want to use Bond energy of Cl2 >> as its quoted in the
Data booklet it should be 242 .. but for Many time i have seen that they are using 244 as the answer !
Why? which data should we quote if the question came to us ?
one of the questions is o'n 2009 va' 41

TheZodiac

6Astarstudent
You shall quote the data according to the booklet given to you. You cannot possible remember all the bond energy values. Besides, most schools provide you with the latest data booklet so you don't have anything to worry about.

help me with part b please
View attachment 36027

how will we figure this out?
When step 1 is the slowest, we only see 1 mole of H2O2, 1 mole of I- and 0 moles of H+. Hence the order is 1,1,0.
When step 2 is the slowest, it means that step one has already taken place and looking at both the equations we can see that we have 1 mole of H2O2 and 1 mole of I- from the 1st equation and 1 mole of H+ as well, from the second equation. Hence the order is 1,1,1.
When step 3 is the slowest, both the previous steps have taken place and have to be taken into account. We see 2 moles of H+, 2 moles of I- and 1 mole of H2O2 from the equations. Hence, the order would be 1,2,2.

i want help too in the same question.
Answered above.
 
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You shall quote the data according to the booklet given to you. You cannot possible remember all the bond energy values. Besides, most schools provide you with the latest data booklet so you don't have anything to worry about.


When step 1 is the slowest, we only see 1 mole of H2O2, 1 mole of I- and 0 moles of H+. Hence the order is 1,1,0.
When step 2 is the slowest, it means that step one has already taken place and looking at both the equations we can see that we have 1 mole of H2O2 and 1 mole of I- from the 1st equation and 1 mole of H+ as well, from the second equation. Hence the order is 1,1,1.
When step 3 is the slowest, both the previous steps have taken place and have to be taken into account. We see 2 moles of H+, 2 moles of I- and 1 mole of H2O2 from the equations. Hence, the order would be 1,2,2.


Answered above.
Thank you!
 
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please please please
I have a questions about the ways to get one isomers in enantiomers of drugs
I need an explanation of getting one isomer using chiral catalyst method , and using optically active starting material method...
Please replay ASAP
Thanks..
 
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al salum allaykom, hello every one , can any one please explain the question 5 (iv) May/June 2010 , I don't understand how the electrode potential of the cathode becomes more negative if less pd ions are present , shouldn't less pd ions mean less oxidation took place , thus the electrode potential should be more positive ?? can any one please explain the whole thing please?
 
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Hey guys...how can get above 30/40 in chemistry P1 .....and what should I do in order to get A* overall in Alevel chemistry...
 
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Hey guys...how can get above 30/40 in chemistry P1 .....and what should I do in order to get A* overall in Alevel chemistry...

once you solve the past pprs from 2004-2012 then u can easily score 30-36 marks easily in that ....
P1 P2 P4 ...score max marks then u can easily get an A*
 
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