difficult to restore the vessel to a condition which will give nornial decomposition rates. Aiccortling to the reactions as written (steps s t through 2 ) tlie rate o f tiisappearaiicc ol C?H,PJr will b e 5ivc.n by the e.upr:wio:i
Ti'he ratii> of (EIBr) t o (CzHj~ is)constant because these two products are kept stoichioinetrically equal as they incrcasc, iluring the course of the reaction. Equation 7 is t h e equntioii oE a first-order rcactioii, and it accmnt-s for the E:ict that this coinples reaction stili f i i r ~ s good c.xpcrinientally detcrniined first-orclcr ratt. constants for t h c ovcrall reaction. The kinetics oi the dcco:1:pusitiori of ethyl broinide and thc varims factors which affect the rate as reported in earlier work appeztr now to be fairly well understood. 'Tlie formation of a halogen by a TI the a k y i halide nntl the hydrogen halide produced by the renctim to give a stcadystate concentration o l ;in ziccelxating intermediate conipound inn!- wdl he '1 Factor in the ki:iet.ics of other alkyl 11:tlitlcs. Acknowledgment. - -'Thi. Liuthors are glad to a?ltnowlcdge assist:incr in Imrt oi the work from sunitncr fe1lowshi;)s iii.i
