1) In the reaction A–>2B, the rate law was determined to be rate=k[A]2 (k=0.1 M-1min-1). When the initial [A]=0.5M, what is the concentration of A after one hour?
2) The half life of 131I is 8 days. How long will it take for 99.9% of a sample containing 131I to decay?
3) reaction A–>2B is first order in A. At time=0s, [A] was 1.0M and [B] was 0M. After 100s, [B] increased to 0.5M. What is the half life of A in this reaction?
4) The first order reaction A–>B+C has a half life (t1/2) of 30 min at 300K and 3min at 400K. What is the activation energy of the reaction? Can somebody show me how to do it step by steps!
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