The rates of aqueous decomposition have been determined for a number of sodium salts of monobromoaliphatic acids in which the position of substitution of the bromine atom ranges from a to y. It has been established that (1) the rates of decomposition, as measured by the release of bromide ion, are of the first order with respect to the ion of the haloacid;(2) the entropies of activation are positive, and, on the average, about 10 eu;(3) the heats of ...