Question

4. For the reaction: (CH3),CBr +1 → (CH3),CI + Br* the following data were collected: (CH3)3Br) (M) Time (s) 0.600 0 0.424 10.0 0.300 20.0 0.212 30.0 0.150 40.0 Determine the rate law for this reaction and calculate the rate constant. (20 points)

Answer 1

Solution is given below. Please go through it. Hope it will help you.

Rate constant for a particular reaction should come same...from any sets of observation . Then only we come to know about order of reaction.
(CH3)3C - BY + 10 (CH3)3 cl + B2C ag t first consider it zero order and calculate rate constant rate constant from all sets of m all sets of observatio is same =) then it is ZERO ORDER CA]. Initial conce к [AJO-[A]t CA] = final conc at time t from 1 and 2 sets K = 0.600-0.424 0.0176 10 from 1 and 3 set Kez 0.600 -0.300 03000015 20 20 mom 2 anda set K 0.4240300 0124 -0.0124 10 dunce k4 K2 K3 = NOT ZERO ORDER Siirlandy consider for FIRST ORDER K = ln [A]. t [A]t

(1) 2 (6 bets I en 0.600 10 0.424 k= -0.0344 (1) & (3) sets ķ= I en 0.600 20 0 300 = 0.0347 (2) & (3) sets KF I en 0.424 10 0.300 = 0.034 6 (4) & (5) sets 0.0346 kg = I en 0.212 10 0 150 same from any of As we can see, rate constant coming set obsowation taken at a time The given Reaction is FIRST ORDER Rate Law = K(CH3)3 Br] -T and rate constant is 0.0346 sec *