Troubles in chem p1

[Jinkglex]

I keep mixing it up, sorry, down the group it does increase

 

[cute97]

PLEASE HELP ME
http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_s12_qp_11.pdf
Q21, Q22, Q23 MARK SCHEME http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_s12_ms_11.pdf
http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_s12_qp_12.pdf
Q16, Q20, Q28 MARK SCHEME http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_s12_ms_12.pdf
http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_w12_qp_11.pdf
Q23, Q17 MARK SCHEME http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_w12_ms_11.pdf
THANKS IN ADVANCE

 

[Dr.MMM]

An organic compound J reacts with sodium to produce an organic ion with a charge of –3.
J reacts with NaOH(aq) to produce an organic ion with a charge of –1.
What could be the structural formula of J?
A HO2CCH(OH)CH2CO2H
B HO2CCH(OH)CH2CHO
C HOCH2CH(OH)CH2CO2H
D HOCH2COCH2CHO

 

[Sara syed]

s11 qp 11 question is a chalenging question pls post the working if u r able workout and get D as the answer

 

[Rabb94]

http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_w12_qp_11.pdf
question-4,11,15
http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_s12_qp_11.pdf
question- 9,13,14
plzzzzzzzzz anyone

 

[Mariam Mohamed SX132]

http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_w10_qp_12.pdf
Q7!!!! PLEASE HELP!

 

[6Astarstudent]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w10_qp_12.pdf
Q7!!!! PLEASE HELP!

Here is a quick equation P1V1 + P2V2 = (total pressure) / (V1 + V2)

so new P = (P1V1 + P2V2)/(V1 + V2) = (5x12 + 10x6) /(5+10) = 120/15 = 8
so correct answer is A

 

[lee mee..]

http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_w10_qp_12.pdf
Q13 anyone??? PLEASE!!

 

[6Astarstudent]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w10_qp_12.pdf
Q13 anyone??? PLEASE!!

This is a disproportion reaction
oxidation number of I in HIO is +1, in I2 is 0 and in HIO3 is +5
so HIO to I2 is (+1 -> 0)x2 which is -2 because there is 2 Is in I2.
and HIO to HIO3 is (+1->+5) which is +4
ratio is -2:4 is 1:2 so mol ratio must be 2:1

 

[lee mee..]

This is a disproportion reaction
oxidation number of I in HIO is +1, in I2 is 0 and in HIO3 is +5
so HIO to I2 is (+1 -> 0)x2 which is -2 because there is 2 Is in I2.
and HIO to HIO3 is (+1->+5) which is +4
ratio is -2:4 is 1:2 so mol ratio must be 2:1

How 1:2 became 2:1 ??

 

[6Astarstudent]

How 1:2 became 2:1 ??

the 1:2 was oxidation number ratio
2:1 is molar ratio

the overall net oxidation number change must be zero.
so (-2) + 4 does not equal to 0
so you have to 2 x (-2) + 1 x (4) = 0
exam is coming soon.. just remember that mol ratio is inversely proportional to oxidation number ratio

 

[lee mee..]

Thank you

 

[Mariam Mohamed SX132]

Here is a quick equation P1V1 + P2V2 = (total pressure) / (V1 + V2)

so new P = (P1V1 + P2V2)/(V1 + V2) = (5x12 + 10x6) /(5+10) = 120/15 = 8
so correct answer is A

Thank you sooooooooooooooo much!

 

[cute97]

ANYONE PLS​

http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_w08_qp_1.pdf Q2 plzz ,Q30 when i do it using ethanol i get 38% while using ethanoic acid i get a different answer which is the correct one 50%??? , Q36 the firts point is correct No. of moles more on reactant side so increasing the pressure will increase the product and kp will increase ???​

Thanks in advance and please answer ​

 

[Mariam Mohamed SX132]

http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_w06_qp_1.pdf
Can someone explain Q11??

 

[6Astarstudent]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w06_qp_1.pdf
Can someone explain Q11??

C2H5OH + CH3CO2H ->CH3CO2C2H5 + H2O
initial mol 1 1 0 0
equilibrium 1-x 1- x x x
K = 4 = x^2/(1-x)^2
square root both sides
2 = x/(1-x)
2(1-x) = x
2-2x = x
x =2/3
which is B

 

[Mariam Mohamed SX132]

C2H5OH + CH3CO2H ->CH3CO2C2H5 + H2O
initial mol 1 1 0 0
equilibrium 1-x 1- x x x
K = 4 = x^2/(1-x)^2
square root both sides
2 = x/(1-x)
2(1-x) = x
2-2x = x
x =2/3
which is B

You are a life saver!!!!!!!!! Thank youuuu

 

[Mariam Mohamed SX132]

http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_s06_qp_1.pdf
Q10

 

[Waleed Amjad]

same doubt here anyone answer plzzz !!

I think its B

 

[HorsePower]

So how was it guys ?