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Please Q23, I cant understand a word.
http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_s12_qp_12.pdf
http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_s12_qp_12.pdf
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Hey guys
could u plz help me with this :s
http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_s12_qp_11.pdf
DOUBTS:
Q2 ----> ANSWER D
Q3 ----> ANSWER D
Q9 ----> ANSWER B
Metanoia
...
The problems are as follows:
In 5 why can't A be correct as it is symmetrical.
In 13 why can't A(Mg) be the answer as when it dissolves the pH is around 6.5 which suggests hydrolysis.
In 23 why can't D(180) be the answer as the chain is like -C-C-C-C-C- which shows the C-C-C bond to be 180.
In 36 why is 2(NH3 behaves as a base) is correct.
In 39, actually I don't get a single point!
Thanks in advance and please try these questions out if possible as they are confusing and they might even help you out!
Thnxs12qp11
Q2. Removing products shift the equilibrium to the right, but does not increase the forward rate of reaction. Please see post #9494 for a sketch explanation.
Q3. Equation can represent both
Heat of formation of water : H2 (g) + 1/2 O2 (g) --> H2O (l) , exothermic
or heat of combustion of H2
Q9. Please check post 9224 on pg 462
FInally, perhaps a simple request to students posting questions here, besides including the answers, it would be more productive to also write down which part of the questions or which of the suggested options you don't understand or agree with. Then it allows those who intend to help to check your understanding.
Something like what browny did here.
thns alot sirUse the 4 options and trial and error.
Before dehydration, the C=C bonds were actually CH-COH.
Check which of the 4 could possibly give us a tertiary alcohol (resistant to oxidation) before dehydration.
In this case, it was D.
View attachment 44341
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w04_qp_1.pdf
Can anybody please explain question 5 ans B, 9 ans B, 12 ans B, 18 ans C, 20 ans A, 38 ans A, please?
Some other problems are in question 11 why can't B be correct, 30 how to draw A and in 31 if a reaction is like from A to B and the energy change is +20 then if the reaction is from B to A is the change -20?
when you add NaOH to a ester , you get a carboxilate salt and alcohol.
W04qp1
Q5. You have to imagine yourself filling up the boxes with 8 electrons. If you follow the rules, you will end up with a final configuration that has the lowest energy level.
Q9. The short answer is, compared other organic compounds with the same number of carbons, burning a hydrocarbon usually gives use the most energy.
The C-O bonds for the rest require a bit more energy to break, compared to one that has only C-H single bonds.
Q11. No change in oxidation states for any atom, cant be redox reaction.
Q12. A boltzman distribution curve for a higher temperature with have its peak shifted to the right, and in a lower height.
Q18. For all the other options, there are dative bonds formed from nitrogen's lone pair.
A. N: -->C
B. N: -->H+
D. N: --> Ag+
Q38.
Y reflects the idea that ppt is formed faster than CH3CH2Cl which gives off 1 Cl- to precipitate with Ag+
1. Formed faster as it gives of 2 Cl-
2. Formed faster as C-Br bond is weaker, so Br- is released faster
3. Formed faster as C-I bond is weaker, so I- is released faster
Can anyone PLEASE explain these question!
Q5,7,17,18,24,25,30,33,34 from
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w05_qp_1.pdf
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w05_ms_1.pdf
I could answer 5,6,25,30,33 if u figure out the rest plz tell me how to solve them as well!
thnks alotwhen you add NaOH to a ester , you get a carboxilate salt and alcohol.
step 1: You break the ester linkage
step 2: write the alcohol and carboxylic acid
step 3: remove H from carboxylic acid and add Na
so you get a alcohol and the carboxilate salt
Therefore answer is B
Thanks so much for the help, I just coudn't figure out thee questions !!!
But in 11 isn't the Cr oxidation number changed.
And in 12 there are others with the curve shifted and with a lower maximum like D for example.
And in 18 how can we know the structure of the compunds such as in D, beacause I think structure of that is not in our syllabus.
help
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