For simplicity if it is assumed that all reactants and products as written are present in an aqueous solution. what is the equilibrium-constant expression in terms of molarities for the aqueous reaction?

The first-order reaction a→2b+c has rate constant 0.538 s−1. if the initial concentration of a is 0.867 mol l−1, what is the half-life of the reaction in seconds? remember to use correct significant figures in your answer (round your answer to the nearest hundredth). do not include units in your response.