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The half-life of lodine- 131 is 8.0252 days and the decay is first order. If 14.4 grams of I-131 is released in Japan and takes 31.8 days to travel across the Pacific, how much I- 131 will be left by the time it reaches California? mass = If the rate constant of a reaction is 0.121s1 at 298K, and 0.362s1 at 308K, what is the activation energy for the reaction? Ea= If the rate constant of a reaction is 2.68s1 at 20C and 9.53s1 at 40C, what is the activation energy for the reaction? Ea= If the rate constant for a reaction is 2.68s1 at 20C and the activation energy is 23.2kJ/mol, then what is the rate at 40C ? Ea= If the rate constant for a reaction is 2.68s1 at 20C and the activation energy is 32.6kJ/mol, then at what temperature will the rate constant have doubled? T=