X+Y→Z From the following data,obtained at 360K,(a)determine the order of the reaction,and(b)determine the initial rate of disappearance of X when the concentration of X is 0.30M and that of Y is 0.40M. Initial rate of disappearance of X [X](M) [Y](M) (M/s) 0.053 0.10 0.50 0.127 0.20 0.30 1.027 0.40 0.60 0.254 0.20 0.60 0.509 0.40 0.30 Solution:Assume that the rate law takes the form Rate=k[XT[Y] Note the data as experiment 1,2,3,4,and 5 in order (a).Take the ratio of the rates from 2&5 and 3&4 experiments,because in these two groups,the concentration of Y are the same,the ratio equals the ratio of the initial rate of disappearance of X. rate3=ae-0.590M/s_k0.40M0°(0.30M rate,rate2x) =20≈4 0.127M1sk0.20M)°(0.30M) + → ZYX From the following data, obtained at 360K, (a) determine the order of the reaction, and (b) determine the initial rate of disappearance of X when the concentration of X is 0.30M and that of Y is 0.40M. Initial rate of disappearance of X (M/s) [X] (M) [Y] (M) 0.053 0.10 0.50 0.127 0.20 0.30 1.027 0.40 0.60 0.254 0.20 0.60 0.509 0.40 0.30 Solution: Assume that the rate law takes the form ba = [Y]k[X]Rate Note the data as experiment 1, 2, 3, 4, and 5 in order (a). Take the ratio of the rates from 2 & 5 and 3 & 4 experiments, because in these two groups, the concentration of Y are the same, the ratio equals the ratio of the initial rate of disappearance of X. 42 )30.0()20.0( )30.0()40.0( /127.0 /590.0 )(2 )(5 2 5 == = ≈= a a b a b x x MMk MMk sM sM rate rate rate rate