## Rate law question

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Dhamnekar Winod
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Joined: Sat Nov 21, 2020 10:14 am
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### Rate law question

(A)The rate law for a certain gaseous reaction is Rate=k[A][C]. If the pressure in the reaction vessel is halved and all other conditions remains the same, the rate of the reaction is decreased by a factor of
(a) 1 (b) 2 (c) 0.5 (d) 0.1

My answer is (a). Is this answer correct? if yes, why it is correct? if no, why it is wrong?

(B)The rate law for a certain gaseous reaction is Rate=k[A][C]. If the pressure in the reaction vessel is tripled and all other conditions remains the same, the rate of the reaction is increased by a factor of
(a) 2 (b) 6 (c) 3 (d) 9

My answer is (d). Is this answer correct? If yes, why it is correct? if no, why it is wrong?
Any science consists of the following process. 1) See 2)Hear 3)Smell,if needed 4)Taste, if needed 5)Think 6)Understand 7)Inference 8)Take decision [Believe or disbelieve, useful or useless, true or false, cause or effect, any other criteria]
ChenBeier
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Posts: 974
Joined: Wed Sep 27, 2017 7:25 am
Location: Berlin, Germany

### Re: Rate law question

a) In my opinion its wrong. Faktor 1 means no change in the reaction rate, this is wrong. But also the other solutions don't fit. In my opinion it's 1/4 = 0.25.
Sum of pA + pC = 0,5p with A = C it's p(0,5)^2 = 0,25 p

b) with the same argument is d correct. Its p(3)^2 = 9 p