Chemistry Forum

(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?

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