3. a) Consider the elementary reaction: A + B C If the reaction proceeds in the presence of a great excess of B i.e. [B] >> [A], write down the rate law for the rate of change of [C] with time. Briefly explain how you deduced this rate law. b) In a separate reaction, compound A reacts to produce compounds B and D, according to the stoichiometric equation: 2A 4B + D The rate law for this reaction is: d[A]/dt = -k[A] Explain what this information tells us about the reaction mechanism of this reaction