Chemistry: Post your doubts here!

[kingo44]

I WANNA WATCH MORE PLEASEEEEEEEEEEEEEEEEEE

 

[student1415]

AS SALAMO ALAIKUM
can some one plzz help me with q 28 , 37 & 39
http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_w04_qp_1.pdf

 

[Thought blocker]

AS SALAMO ALAIKUM
can some one plzz help me with q 28 , 37 & 39
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w04_qp_1.pdf

28)
1 u know is right
2) when two ethane radicals combine
3) when combination of ethane radical is chlorinated

37)
Remember the termination step. Two free radicals join to form a molecule. Break this molecule CH3CHCl-CHClCH3 into this CH3*CHCl and *CHClCH3. These are two free radicals formed in the propagation step. Whenever these questions come. Break the central bond and check if two free radicals are formed.

39)
♣♠ Magnanimous ♣♠

 

[not.maria]

http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_s12_qp_11.pdf

Can someone explain Q 2, 9, 13 ,14, 22 and 36
Thanks!

 

[DeViL gURl B)]

http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_s11_qp_32.pdf

HELP!!! how do we calculate the enthalpy change??!! :$
Question 2 b (iii)

 

[♣♠ Magnanimous ♣♠]

AS SALAMO ALAIKUM
can some one plzz help me with q 28 , 37 & 39
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w04_qp_1.pdf

it's simple!
see 39) when there is an OH the reaction can occur with sodium metal and that is given in the book which means tatement 1 is CORRECT!
statement 3) overall molecular formula is C5H12O4 so it cannot be CH3O which means this is wrong and due to this statement 2 is also eliminated so answer is D

 

[DeViL gURl B)]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_s11_qp_32.pdf

HELP!!! how do we calculate the enthalpy change??!! :$
Question 2 b (iii)

Guys.. Any help???
Plus question 3 (b) as well!! The ion part! Pleaaasseeeee!!!

 

[♣♠ Magnanimous ♣♠]

Thought blocker dude! I need your help in one thing of enthalpy calculation if online do reply?
OR ANY ONE CAN REPLY IF AVALIABLE!

 

[Thought blocker]

Thought blocker dude! I need your help in one thing of enthalpy calculation if online do reply?
OR ANY ONE CAN REPLY IF AVALIABLE!

Wait, I have loads of work... Will come to your house, or will do it tomorrow

 

[♣♠ Magnanimous ♣♠]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w06_qp_1.pdf
Plz help me with 3 questions from o/n/6
Q9-C
Q11-B
Q25-B
Thanku

well i am not sure about 9 amd 11
25) it should be B na bcoz there are 3n carbon and 6n Hydrogen so if we balance the equation we get 9 moles of oxygen on the product side so for balancing the moles of oxygen in reactact obviously it should 4.5 because it already O2 so simple calculation for verfication --> 4.5 *2 ==> 9 so the overall equation is balanced
I hope you got it!

 

[♣♠ Magnanimous ♣♠]

Wait, I have loads of work... Will come to your house, or will do it tomorrow

bro it is simple calculation needed! you know na my maths probs so. and this is enthalpy calculations! it will hardly take 2 min for you

 

[Thought blocker]

bro it is simple calculation needed! you know na my maths probs so. and this is enthalpy calculations! it will hardly take 2 min for you

Post it, if I would be free, I'd solve it. Go on!

 

[♣♠ Magnanimous ♣♠]

Post it, if I would be free, I'd solve it. Go on!

As you know that for finding entalpy we substract ==> product - reactant
than solve this for me .. hey me bhu gaya kiska doubt tha ruk do min ab
i got sweet sugar post ques 9 cmon bro do it!

 

[Thought blocker]

As you know that for finding entalpy we substract ==> product - reactant
than solve this for me .. hey me bhu gaya kiska doubt tha ruk do min ab
i got sweet sugar post ques 9 cmon bro do it!

Link ?

 

[♣♠ Magnanimous ♣♠]

ah

Link ?

hhhhh ok
http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_w06_qp_1.pdf
ques 9

 

[not.maria]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w06_qp_1.pdf
Plz help me with 3 questions from o/n/6
Q9-C
Q11-B
Q25-B
Thanku

q9


q 11 assume the moles used up were x.


so u have equation

4= x^2/(1-x)^2

taking square roots on both sides we have

2=x/(1-x)

2-2x=x

2/3 =x


since volume is not mentioned you can assume it to be 1 dm^3

 

[♣♠ Magnanimous ♣♠]

q9

q 11 assume the moles used up were x.

so u have equation

4= x^2/(1-x)^2

taking square roots on both sides we have

2=x/(1-x)

2-2x=x

2/3 =x


since volume is not mentioned you can assume it to be 1 dm^3

where the square come from in ques 11

 

[Thought blocker]

ah

hhhhh ok
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w06_qp_1.pdf
ques 9

Okay, here goes:

CO2(g) + H2(g) -> CO(g) + H2O(g)

CO2 is being broken, so instead of -283, we take +283
H2O is being formed, so we use -286
BUT it is being formed in gaseous state, not liquid state, so we also take +44.

283 + 44 - 286 = +41.

So the answer is C

 

[♣♠ Magnanimous ♣♠]

Okay, here goes:

CO2(g) + H2(g) -> CO(g) + H2O(g)

CO2 is being broken, so instead of -283, we take +283
H2O is being formed, so we use -286
BUT it is being formed in gaseous state, not liquid state, so we also take +44.

283 + 44 - 286 = +41.

So the answer is C

sorry but muje kuch samaj me nahi aya

 

[ZaqZainab]

http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_w06_qp_1.pdf
Q1
Q11
Q13 how exactly?
Q14
Q16 doesn't it give white ppt?
Please help