1) The Arrhenius parameters for the gas-phase decomposition of cyclobutene, C4H8(g) 2C2H4(g), are A = 4 1015 s -1 and Ea = 261 kJ/mol. Determine (a) the rate constant, kr and (b) the half-life of cyclobutene at 20 and 50 .

2) The initial concentration of a reactant A in a zeroth order reaction (A P) is 0.75M. The rate constant kr is 0.015 M/s. (a) what will be the concentration of the reactant after 15 seconds? (b) how long will it take the concentration to be reduced to 0.06 M?