Average Lifetime of Kinetic Chains

The average lifetime (r) of the kinetic chain is given by the ratio of the steady-state radical concentration to the steady-state rate of radical disappearance  

Problem 6.16 In an experiment, styrene polymerization in bulk at 60°C is initiated by 1x10 M benzoyl peroxide. The density of liquid st3n ene is 0.909 g/cm at the reaction temperature. What is the average radical lifetime and what is the steady-state radical concentration [Data at 60°C kt (styrene) = 6.0x10 L mol s kd (benzoyl peroxide) = 7.1x10 s h / = 0.5.] 

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