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Chemistry Paper 4-theory- doubts =D

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http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w11_qp_41.pdf

Q 2(a)
Can somebody please tell me how to calculate the order with respect to H+??
Thank you very much.
Jazakum Allahu Khair!
Okay, see
We know that order of reaction of CH3CHO is one
so since it decrease from
0.25 to 0.2
so 0.25/0.2
=5/4
so basically the rate, must have decrease from 2 to 1.6 (2 x 4/5)

now we consider the change due to H is from 1.6 to to 3.2
and 3.2/1.6 is 2
and 0.1/0.05 is 2
so order is 1
 
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Okay, see
We know that order of reaction of CH3CHO is one
so since it decrease from
0.25 to 0.2
so 0.25/0.2
=5/4
so basically the rate, must have decrease from 2 to 1.6 (2 x 4/5)

now we consider the change due to H is from 1.6 to to 3.2
and 3.2/1.6 is 2
and 0.1/0.05 is 2
so order is 1
Jazak Allahu Khair!:):)
But how did you get 1.6?
 
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or anyone online....please...


If it is the one where you have to state the units of the rate constant, then:

The units of rate of reaction mol dm^-3 s^-1.
The reaction is first order with respect to each reactant involved, so to ensure that the units on the left of the equation are equal to the units on the right side,

mol dm^-3 s^-1 = k * (mol dm^-3)(mol dm^-3)(mol dm^-3)

Cancelling units from both sides,

s^-1 = k * (mol dm^-3)(mol dm^-3)

Rearranging for k,

mol^-2 dm^6 s^-1 = k

Therefore the units of the rate constant are mol^-2 dm^6 s^-1.

Hope this helped!
Good Luck for all your exams!
 
Messages
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If it is the one where you have to state the units of the rate constant, then:

The units of rate of reaction mol dm^-3 s^-1.
The reaction is first order with respect to each reactant involved, so to ensure that the units on the left of the equation are equal to the units on the right side,

mol dm^-3 s^-1 = k * (mol dm^-3)(mol dm^-3)(mol dm^-3)

Cancelling units from both sides,

s^-1 = k * (mol dm^-3)(mol dm^-3)

Rearranging for k,

mol^-2 dm^6 s^-1 = k

Therefore the units of the rate constant are mol^-2 dm^6 s^-1.

Hope this helped!
Good Luck for all your exams!
Right!! Jazak Allahu Khairan! Yes it has!:)
May Allah bless you!
Thank you! Good Luck to you too inshAllah:):)
 
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If it is the one where you have to state the units of the rate constant, then:

The units of rate of reaction mol dm^-3 s^-1.
The reaction is first order with respect to each reactant involved, so to ensure that the units on the left of the equation are equal to the units on the right side,

mol dm^-3 s^-1 = k * (mol dm^-3)(mol dm^-3)(mol dm^-3)

Cancelling units from both sides,

s^-1 = k * (mol dm^-3)(mol dm^-3)

Rearranging for k,

mol^-2 dm^6 s^-1 = k

Therefore the units of the rate constant are mol^-2 dm^6 s^-1.

Hope this helped!
Good Luck for all your exams!
what about b(i) and (ii)??
 
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