We were just going over examples of reaction orders in class and I was told 2 things: 1.) Negative reaction orders are possible 2.) An order of 0 says the reaction rate is independent of the reactant concentration(s) I had a few questions, though. 1.) What exactly constitutes a negative order reaction if reaction orders are determined by the RDS in elementary steps? Are reactants being produced when the forward reaction occurs? What exactly is going on for this to occur? 2.) If the order of the reaction is 0, but one reactant has an order of -1/2 and the other 1/2, doesn't this still mean that the reaction rate is dependent on reactant concentration despite having an overall order of 0? Any clarification please? Thanks!