The reaction,[Co(NH_(3))_(5)Br]^(2+)+H_(2)Orarr[Co(NH_(3))_(5)(H_(2)O)]^(3+)+Br^(-) is folllowed by measuring a property of the solution known as the optical density of which may be taken to be linearly related to the concentration of the reactant. The values of optical density are 0.80,0.35 and 0.20 at the end of 20 minutes, 40 minutes and infinite time after the start of the reaction which is first order. Calculate the rate constant.

The reaction,[Co(NH_(3))_(5)Br]^(2+)+H_(2)Orarr[Co(NH_(3))_(5)(H_(2)O)

1.	The reaction,[Co(NH_(3))_(5)Br]^(2+)+H_(2)Orarr[Co(NH_(3))_(5)(H_(2)O)]^(3+)+Br^(-) is folllowed by measuring a property of the solution known as the optical density of which may be taken to be linearly related to the concentration of the reactant. The values of optical density are 0.80,0.35 and 0.20 at the end of 20 minutes, 40 minutes and infinite time after the start of the reaction which is first order. Calculate the rate constant.
Answer» `6.93xx10^(-3)MIN^(-1)` `3.51xx10^(-2)min^(-1)` `6.93xx10^(-2)min^(-1)` `3.51xx10^(-3)min^(-1)` ANSWER :C